THE  UNIVERSITY 


OF  ILLINOIS 


GRICULTURE 


NON  CIRCULATING 

i’- 

CHECK  FOR'  UNBOUND 

circulating  coax 


Bulletin  102. 


August,  1905 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College, 


Feeding  Steers 

On 

Sugar  Beet  Pulp, 
Alfalfa  Hay  and 
Ground  Corn. 


BY  W.  L.  CARLYLE  AND  C.  J.  GRIFFITH. 


PUBLISHED  BY  THE  EXPERIMENT  STATION 


Fort  Collins,  Colorado. 
1  905. 


THE  AGRICULTURAL  EXPERIMENT  STATION, 


FORT  COLLINS,  COLORADO. 


The  State  Board  of  agriculture. 


Hon.  P.  F.  SHARP,  President , . 

Hon.  HARLAN  THOMAS, 

Hon.  JAMES  L.  CHATFIELD, 

Hon.  B.  U.  DYE, . 

Hon.  B.  F.  ROCKAFELLOW 
Hon.  EUGENE  H.  GRUBB, 

Hon.  A.  A.  EDWARDS,  ----- 
Hon.  R.  C.  CORWIN,  -  - 

Governor  JESSE  L.  McDONALD,  / 
President  BARTON  O.  AYLESWOKTH,  \)ex'°lJlC10 


TERM 


Denver 

EXPIRES 

-  1907 

Denver,  - 

-  1907 

Gypsum,  - 

-  1909 

Rockyford, 

1909 

Canon  City 

1911 

Carbondale, 

-  1911 

Fort  Collins, 

1913 

Pueblo 

1913 

Executive  Committee  in  Charge 

P,  F:  SHARP,  Chairman.  B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS. 


Station  staff. 

L.  G.  CARPENTER,  M.  S.,  Director  -  -  -  Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S., . Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D., . Chemist 

W.  PADDOCK,  M.  S., . Horticulturist 

W.  L.  CARLYLE,  M.  S., . Agriculturist 

G.  H.  GLOVER,  B.  S.,  D.  V.  M., . Veterinarian 

C.  J.  GRIFFITH,  B.  S.  A., . •  Animal  Husbandman 

W.  H.  OLIN,  M.  S., . Agronomist 

R.  E.  TRIMBLE,  B.  S.,  -  -  -  Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  B.  S.,  ------  -  Assistant  Chemist 

EARL  DOUGLASS,  B.  S.,  . Assistant  Chemist 

A.  H.  DANIELSON,  B.  S., . Assistant  Agriculturist 

S.  ARTHUR  JOHNSON,  M.  S.,  -  -  -  -  Assistant  Entomologist 

B.  O.  LONGYEAR,  M.  S.,  -  -  -  -  Assistant  Horticulturist 

P.  K.  BLINN,  B.  S.,  -  -  Field  Agent,  Arkansas  Valley,  Rockyford 


OFFICERS. 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S., . Director 

A.  M.  HAWLEY, . Secretary 

MARGARET  MURRAY,  -  -  -  Stenographer  and  Clerk 


university  of  iitiNCia 
agriculture  library 


6>  3 o.l 
C  1 1  b 

VL(?  ,  I  6  ~  ?  6 


THE  VALUE  OF  SUGAR  BEET  PULP,  ALFALFA  HAY  AND 
GROUND  CORN  IN  FATTENING  STEERS.* 


By  W.  L  Carlyle  and  C  J.  Griffith. 

In  bulletin  number  97  of  this  Station  is  given  the  results  of 
an  experiment  which  was  undertaken  for  the  purpose  of  determi¬ 
ning  if  sugar  beet  pulp  is  a  suitable  foo^  when  fed  with  alfalfa  hay 
and  farm  grains  for  beef  production.  The  results  obtained  were 
not  considered  final,  though  of  importance  as  indicating  that  sugar 
beet  pulp  when  fed  in  combination  with  alfalfa  hay  and  farm 
grains  will  produce  an  excellent  quality  of  beef  at  a  very  low  cost. 

The  object  of  the  experiment  here  reported  was  to  determine 
more  fully  the  comparative  value  of  alfalfa  hay,  sugar  beet  pulp 
and  corn,  when  fed  singly  and  in  various  combinations  to  ordinary 
range  steers. 

Plan  of  Experiment. 

In  planning  the  experiment  we  had  the  hearty  co-operation  of 
the  Fort  Collins-Colorado  Sugar  Company,  through  its  manager, 
Mr.  R.  M.  Booraem,  to  whom  the  station  is  greatly  indebted  for 
many  courtesies,  as  well  as  the  stock,  feed,  corrals,  labor,  and  all 
necessary  conveniences  for  conducting  the  experiment. 

The  forty-eight  steers  selected  for  the  experiment  were  taken 
from  a  lot  that  had  been  fed  on  alfalfa  hay  and  beet  pulp  for  some 
weeks,  and,  previous  to  that  time,  had  been  ranging  on  the  beet 
fields  and  feeding  upon  beet  tops.  They  were  of  mixed  breeding, 

*Other  bulletins  relating  to  the  feeding  of  Sugar  Beets  and  Sugar  Beet  Pulp  have 
bee  i  published  by  the  Experiment  Station,  and  may  be  had  on  request  of  the  Director. 

73. — Hart  1.— Feeding  Value  of  Beet  Pulp.  Part  2— Feeding  Beet  Pulp  and  Sugar 
Beets  to  Cows.  By  Buffum  and  Griffith,  1902. 

74. — Swine  Feeding.  By  Buff  i in  and  Griffith,  1902, 

75.  Lamb  Feeding  Experiment.  By  Buffum  and  Griffith,  1902. 

77.— Feeding  Beet  Pulp  to  Lambs.  H.  H.  Griffin,  1902. 

9?.— Feeding  Steers  on  Sugar  Beet  Pulp.  Carlyle,  Griffith  and  Meyer,  1905. 


STATE  AGRICULTURAL  COLLEGE. 


4 

Shorthorn  and  Hereford  blood  predominating,  and  were  below  the 
average  in  quality.  They  were  two  years  of  age  with  one  or  two 
in  each  lot  probably  three  years  past.  When  the  experiment  was 
started  on  December  30,  these  steers  averaged  in  weight  between 
950  and  960  pounds.  They  were  divided  as  evenly  as  possible  into 
four  lots  of  twelve  each,  care  being  taken  to  have  an  equal  number 
of  promising  and  unpromising  feeders  in  each  lot.  .  They  were  con¬ 
fined  in  four  small  corrals  in  close  proximity  to  the  Fort  Collins 
sugar  factory,  water  being  provided  in  a  large  trough,  a  portion  of 
which  projected  into  each  corral.  The  fences,  feed  racks  and  feed 
boxes  provided  for  the  pulp  and  grain  were  such  as  are  used  for 
this  purpose  by  all  feeders  in  Northern  Colorado. 

The  different  rations  to  be  fed  were  as  follows: 

Lot  I. — Alfalfa  hay,  beet  pulp  and  ground  corn. 

Lot  II.— Alfalfa  hay  and  ground  corn. 

Lot  III. —Alfalfa  hay  and  beet  pulp. 

Lot  IV. — Alfalfa  hay. 

The  alfalfa  hay  was  fed  ad.  libitum  to  the  steers  in  each  of  the 
lots  and  was  weighed  in  bulk  as  it  was  hauled  to  the  corrals  and 
placed  in  a  small  enclosure  where  it  could  be  readily  forked  close 
to  the  feed  rack,  from  which  place,  on  the  ground,  it  was  eaten. 
This  system  of  weighing  the  feed  in  large  quantities  accounts  for 
the  wide  variation  in  amounts  charged  to  the  steers  in  the  various 
week-periods  of  the  experiment. 

The  hay  was  much  below  the  average  of  the  best  Northern 
Colorado  alfalfa  hay,  as  it  was  very  coarse  as  a  rule  and  had  been 
much  spoiled  in  curing. 

The  pulp  fed  to  Dots  1  and  III  was  also  fed  ad.  libitum  and 
was  placed  fresh  in  the  feed  boxes  or  u bunks”  twice  each  day. 

The  corn  was  of  good  quality,  and  was  rather  coarsely  ground 
in  a  local  mill,  being  fed  in  limited  quantities  once  each  day  just 
after  noon.  The  amount  of  corn  meal  fed  was  very  small  at  the 
beginning,  but  was  gradually  increased.  Two  pounds  per  head 
was  given  the  first  week,  three  pounds  the  second  week,  and  four 
pounds  during  the  third  and  fourth  weeks.  Five  pounds  was  given 
during  the  fifth  and  sixth  weeks,  and  eight  pounds  during  the 
seventh  and  eighth  weeks,  after  which  the  amount  was  increased 
gradually  until  the  last  two  weeks  of  the  experiment,  when  each 
steer  on  the  average  in  the  two  lots  received  eleven  pounds  daily. 
The  amount  of  corn  meal  for  each  week’s  feeding  was  weighed  out 
in  advance,  and  approximately  the  same  amount  was  fed  each  day, 
care  being  taken  to  see  that  all  was  fed  out  during  the  week,  and 
as  evenly  apportioned  as  possible  daily  by  measure. 

The  steers  in  each  lot  were  weighed  on  Saturday  of  each  week, 
the  weights  being  recorded  as  they  were  taken. 


FEEDING  STEERS  ON  BEET  PUEP,  AEFAEEA  PAY  AND  CORN 


5 


Total  Feed,  Weight  and  Gain,  With  Average  Weight 

and  Gain  of  Each  Steer, 


Table  1. — Lot  I.  Fed  Beet  Pulp,  Hay  and  Ground  Corn. 


Date. 

Pulp. 

Hay. 

Corn. 

Total 

Weight. 

Total 

Gain. 

Average 

Weight. 

Av.  Weekly 
Gain. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

Dec.  30 . 

11415 

951 

Jan.  7 . 

9830 

6315 

216 

12210 

795 

1018 

66 

“  14 . 

6980 

2580 

252 

12405 

195 

1034 

16 

“  21 . 

8895 

785 

336 

12260 

—145 

1022 

-12 

“  28  ...  . 

10170 

830 

336 

12365 

105 

1030 

6 

Feb.  4 . 

8830 

1290 

420 

12840 

475 

1070 

40 

“  11 . 

5220  i 

2905 

420 

* 

18  . 

8617 

1000 

588 

13120 

280 

1093 

23 

"  25 . 

7819 

2475 

588 

13075 

—  45 

1090 

—  3 

Mar.  4 . . 

6135 

672 

13425 

350 

1119 

29 

“  11 . 

7447 

672 

13800 

375 

1150 

31 

18 . 

9331 

1555 

750 

14110 

310 

1176 

26 

•“  25 . 

8815 

2360 

840 

14220 

110 

1185 

9 

Apr.  1 . 

6113 

1900 

924 

11645 

425 

1220 

35 

8 . 

7285 

924 

14578 

—  67 

1215 

—  5 

Total . 

112117 

23995 

7944 

14578 

3163' 

19 

* 

*not  weighed, 


Table  II.- — Lot  II.  Fed  Hay  and  Ground  Corn. 


Dec. 

30 

Jan. 

7 

66 

14 

66 

21. 

66  ’ 

28. 

Feb. 

4 

if 

11. 

(1 

18. 

66* 

25 

M|ir. 

4. 

11. 

66 

18. 

(f6 

25. 

AHr- 

1. 

8. 

Total 


Date. 


*not  weighed. 


Hay. 

Corn. 

Total 

Weight. 

Total 

Gain. 

Average 

Weight. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

11615 

968 

6530 

216 

1214u 

525 

1012 

2870 

252 

12365 

225 

1030 

2725 

336 

12420 

65 

1035 

1920 

386 

12295 

—125 

1025 

8050 

420 

12760 

455 

1063 

4120 

420 

* 

2430 

588 

12976 

215 

1081 

2105 

588 

12750 

—225 

1093 

1005 

672 

12995 

245 

1083 

1005 

672 

13285 

290 

1107' 

1550 

856 

13520 

235 

1127 

3290 

840 

13535 

15 

H'28 

2980 

924 

13725 

M0 

1144 

1940 

924 

13725 

. . 

0 

U44 

37520 

7944 

13726 

2110  ’ 

Av.  Weekly 
Gain. 


lbs. 


44 

18-  ; 
5  ' 
) 

i 


-10 

38 


-18-  ' 
-18 
2&> 
24- 
2$ 
i 

46 


6 


STATE  AGRICULTURAL  COLLEGE. 


Table  111. — Lot  III.  Fed  Beet  Pulp  and  Hay. 


Date. 

Pulp. 

Hay. 

Total 

Weight. 

Total 

Gain. 

Average 

Weight. 

Av.  Weekly 
Gain. 

Dec.  30 . 

lbs. 

lbs. 

lbs. 

11290 

lbs. 

lbs. 

941 

lbs. 

Jan.  7 . . . 

11630 

5375 

11850 

560 

988 

47 

“  14 . 

7700 

2580 

12110 

260 

1009 

21 

“  21 . 

9055 

785 

11990 

—120 

999 

—10 

“  28 . 

11065 

830 

12050 

60 

1004 

5 

Feb.  4... . 

“  11 . 

9550 

5220 

1290 

2905 

12260 

* 

210 

1022 

18 

“  18 . 

8617 

1060 

12460 

200 

1036 

16 

“  25  . 

7849 

865 

12625 

165 

1052 

14 

Mar.  4 . 

7165 

1650 

12735 

110 

1061 

9 

“  11 . 

7447 

1055 

13035 

300 

1086 

25 

“  18  . 

9331 

945 

13310 

275 

1109 

23 

“  25 . 

8730 

3610 

13265 

—  45 

1105 

—  4 

Apr.  1 . 

“  8 . 

6113 

1500 

1859Q 

325 

1132 

27 

7285 

1880 

13500 

-  90 

1125 

—  7 

Total  . . 

11677 

26270 

13500 

2210 

13.1 

*not  weighed. 


Table  IV. -Lot  IV.  Fed  Hay. 


Date. 

Hay. 

Total 

Weight. 

Total 

Gain. 

Average 

Weight. 

Av.  Weekly 
Gain. 

Dec.  30 . 

lbs. 

lbs. 

11620 

lbs. 

lbs. 

962 

lbs. 

Jan.  7 . 

8970 

12515 

695 

1026 

58 

“  14 . 

3380 

12480 

165 

1040 

14 

“  21 . : . 

2465 

12375 

-105 

1031 

-  9 

28 .  . 

3340 

12480 

105 

1040 

9 

Feb.  4 . 

“  11 . 

■2820 

3940 

12515 

* 

35 

1043 

3 

“  18 . 

1480 

12655 

140 

1055 

12 

"  25 . 

2780 

12665 

230 

1074 

19 

Mar.  4 . 

2540 

12795 

—  90 

1066 

—  8 

“  11 . 

2260 

13245 

450 

1104 

38 

“  18 . 

3165 

13155 

-  90 

1096 

—  8 

“  25 . 

4250 

13340 

185 

1112 

16 

Apr.  1 . 

*  8 . 

5165 

13295 

—  45 

1108 

—  4 

3420 

13380 

95 

1115 

8 

Total . 

49795 

13380 

1760 

10.5 

*not  weighed. 


In  tables  I  to  IV  is  given  the  data  in  tabulated  form  of  the 
amounts  of  feed  eaten  by  the  steers  in  each  of  the  lots;  also  the 
gains  made  each  week  by  each  lot.  As  was  the  case  in  similar  data 
given  in  bulletin  No.  97,  relating  to  the  feeding  of  steers,  there 
were  a  number  of  weekly  weighings  when  the  steers  in  each  lot 
showed  a  loss  as  compared  with  the  weights  given  the  week  pre¬ 
vious.  In  this  experiment,  however,  there  was  apparently  no  spe¬ 
cific  cause  for  the  variation  in  the  thrift  of  the  animals.  I11  the 
preceding  experiment  the  steers  in  the  different  lots  appeared  to 
gain  or  lose  weight  in  unison,  but  in  this  case  there  was  more  varia¬ 
tion  in  the  different  lots  from  week  to  week,  it  being  more  apparent 
in  Lot  IV,  in  which  the  steers  were  fed  only  hay.  The  great  varia¬ 
tion  in  rate  of  gain  in  this  lot  might  be  accounted  for  by  the  more 
variable  appetite  of  the  animals  when  fed  on  a  single  kind  of  feed, 
while  the  steers  in  the  other  lots  that  were  receiving  a  mixed  ration 


feeding  steers  on  beet  pulp,  alfalfa  hay  and  corn.  7 

would  be  more  likely  to  have  a  greater  relish  for  their  food  at  all 
times. 

It  will  be  observed  that  the  steers  in  Lot  I  that  received  a 
mixed  ration  composed  of  pulp,  alfalfa  hay  and  ground  corn  made  an 
average  weekly  gain  of  19  lbs.  during  the  experiment,  or  an  aver¬ 
age  daily  gain  for  each  steer  of  2.7  lbs.  The  steers  in  Lot  II  re¬ 
ceiving  alfalfa  hay  and  ground  corn,  the  amount  of  the  latter  feed 
being  exactly  the  same  as  was  received  by  the  steers  in  Lot  I,  made 
a  gain  of  but  12.6  lbs.  per  week,  or  an  average  daily  gain  of  but  1.8 
lbs.,  a  difference  of  .9  of  a  pound  in  the  average  daily  gain  of 
each  steer.  The  steers  in  Lot  III,  receiving  pulp  and  alfalfa  hay, 
made  an  average  weekly  gain  of  13.1  lbs.,  or  an  average  daily  gain 
of  1.9  lbs.,  and  received  no  grain  of  any  kind  during  the  experiment. 

The  steers  in  Lot  IV  that  received  nothing  but  alfalfa  during 
the  entire  experiment  made  an  average  weekly  gain  of  10.5  lbs. 
or  an  average  daily  gain  on  each  steer  of  1.5  lbs. 

For  this  experiment,  the  prices  charged  for  feed  were  such  as 
the  average  feeder  paid  in  the  vicinitv  of  Fort  Collins,  viz.,  alfalfa 
hay,  $5.00  per  ton;  corn,  85  cents  per  cwt.,  and  beet  pulp  at  50 
cents  per  ton.  The  pulp  was  received  from  the  sugar  factory  at  a 
cost  of  35  cents  per  ton.  As  there  is  much  more  labor  entailed 
in  feeding  steers  on  pulp  than  where  alfalfa  hay  and  ground  corn 
only  are  fed,  we  charged  the  pulp  up  to  the  steers  at  50  cents  per 
ton,  allowing  15  cents  per  ton  above  market  price  for  the  difference 
in  cost  of  labor  in  feeding  pulp  over  the  cost  of  labor  in  feeding  hay 
and  corn. 

Table  V. — Average  Amount  Feed  Required  lor  One  Pound  of  Gain, 

and  Cost  of  the  Same 


Food' Fed. 

Cost. 

Alfalfa. 

Pulp. 

Corn 

Meal. 

lbs. 

lbs. 

lbs. 

cts. 

Lot  1 . 

7.59 

35.45 

2.51 

4.22 

Lot  2 . 

17.78 

3.78 

7.63 

Lot  3 . 

11.89 

52.83 

4.28 

Lot  4 . 

28.29 

7.04 

In  table  V  is  given  the  data  showing  the  amounts  of  the  va¬ 
rious  kinds  of  feed  required  to  produce  a  pound  of  live  weight  gain 
on  a  rather  rough  bunch  of  steers  rising  three  years  old.  From 
this  table  it  will  be  seen  that  in  case  of  Lot  IV  it  required  28.29 
lbs.  of  alfalfa  hay,  below  the  average  in  quality,  to  produce  one 
pound  of  gain.  With  an  average  lot  of  good  feeding  steers,  and 
alfalfa  hay  of  good  feeding  quality,  the  indications  are  that  one 
pound  of  gain  would  be  produced  for  each  25  lbs.  of  alfalfa  hay  on 
the  average. 

When  beet  pulp  ad.  libitum  was  added  to  the  ration  of  alfalfa 
hay  in  the  case  of  Lot  III,  the  amount  of  the  latter  required  for  a 


8  STA'i'B  AGRICULTURAL  C6tU3Glb 

pound  of  gain  was  reduced  to  ii;§9  pounds,  th<*  steers  requiring* 
32.83  pounds  of  beet  pulp  to  replace  16.4  pounds  of  hay  in  produc¬ 
ing  a  pound  of  gain.  In  other  words  3.22  pounds  of  beet  pulp 
wheii  fed  to  steers  in  combination  with  alfalfa  hay  are  equivalent 
to  one  pound  of  hay  in  feeding  value,  when  the  hay  is  fed  as  the 
entire  ration.  With  alfalfa  hay  selling  at  $5  per  ton,  beet  pulp  is 
therefore  worth  1.59  cents  per  ton  to  combine  with  alfalfa  in  the 
production  of  beef. 

By  adding  ground  corn  to  the  ration  of  alfalfa  hay  in  the  case 
of  Lot  II,  it  will  be  seen  that  3.76  lbs.  of  ground  Corn  when  added 
to  the  ration  of  alfalfa  hay  resulted  in  deducing  the  amount  of  hay 
tequired  for  one  pound  of  gain  from  28.29  lbs.  to  17.78  lbs.,  the 
steers  in  this  lot  requiring  3.76  lbs.  of  ground  corn  to  replace  10.5! 
lbs*  of  hay  in  producing  a  pound  of  gain.  In  this  case  3.76  lbs.  of 
Corn  was  equivalent  to  10.51  lbs.  of  hay-,  of  one  pound  of  corn  was 
equal  in  feeding  to  2.8  lbs.  of  hay  when  fed  ill  conjunction  with  a 
ration  of  alfalfa  hay  in  fattening  steers.  With  alfalfa  hay  selling 
at  $5  per  ton,  ground  corn,  according  to  the  results  of  this  trial, 
should  be  worth  at  least  $17.85  per  ton,  which  indicates  that  corn 
at  85  cents  per  hundred  could  be  fed  with  practically  equal  profit 
with  alfalfa  hay  at  $5  per  ton. 

In  Lot  I,  where  both  ground  corn  and  beet  pulp  was  added  to 
the  hay  ration,  it  will  be  seen  that  the  amount  of  hay  required  for 
a  pound  of  gain  was  reduced  to  7.59  lbs.,  this  reduction  being  ac¬ 
complished  by  the  use  of  35.45  lbs.  of  pulp  and  2.51  lbs.  of  ground 
corn.  We  have  seen  from  the  comparison  of  nutrient  values  in 
pulp  and  hay,  in  the  case  of  Lots  III  and  IV,  that  one  pound  of  hay 
was  equivalent  to  3.22  lbs.  of  pulp,  and  from  the  data  in  the  case  of 
Lots  II  and  III,  that  one  pound  of  corn  was  equivalent  to  2.8  lbs.  of 
alfalfa  hay,  consequently  by  reducing  the  amounts  of  pulp  and  corn, 
fed  in  conjunction  with  hay  to  the  steers  in  Lot  I,  to  their  equiva¬ 
lent  in  hay,  we  should  find,  other  things  being  equal,  that  this, 
gether  with  the  hay  fed  to  Lot  1,  should  equal  the  amount  uf  fety 
required  by  the  steers  in  Lot  IV  for  the  production  of  a  pound  of  gain. 

It  has  been  shown  that  3.22  pounds  of  pulp  equaled  one  pound 
hay;  therefore  35.45  pounds  of  pulp  is  equal  to  o  pounds,  of  bay-.. 
We  have  also  seen  that  one  pound  of  corn  is  equal  to  2.8  pounds  oft 
hay,  therefore  2.51  pounds  of  corn  is  equal  to  7.03  pounds  of  hay: 
The  steers  in  Lot  I  therefore  had  the  equivalent  of  n  pounds  of; 
hay  in  the  pulp  fed  them,  and  the  equivalent  of  7.03  pounds  of  hay- 
in  the  corn  fed,  which,  together  with  the  amount  of  hay  actually 
fed,  amounting  to  7.59  pounds,  makes  a  total  of  25.62  pounds  of 
hay  required  for  one  pound  of  live  weight  gain.  Since  the  steers 
in  Lot  I  required  28:29  pounds  of  hay  for  one  pound  of  gain,  we 
therefore  have  a  balance  of  2.67  pounds  of  hay  or  9.43  per  cent,  as  the 
amount  saved  by  feeding  steers  a  combination  of  feeds  rather  than 
one  kind  singly. 


.FEEDING  STEERS  ON  BEET  PULP,  ALFALFA  HAY  AND  CORN.  Q 


Table  VI.— Showing  the  Average  Weights  and  Gains.  Also  the  Average  Amount  of  Feed 

Eaten  and  the  Average  Cost  per  Head  for  100  Days. 


Average 
Weight 
at  Be¬ 
ginning. 

Average 
Weight 
at  End. 

Avei*age 

Gain 

Made. 

Food  Fed  Per  Head. 

Cost  of 
Feed 
Per 
Head. 

Alfalfa. 

Pulp. 

Corn 

Meal. 

Lot  1 . 

951 

1215 

263 

1999 

9343 

662 

$12.95 

Lot  2^...  .  . 

968 

1114 

176 

3137 

662 

18.43 

Lot  3 . 

941 

1125 

184 

2189 

9729 

7.90 

Lot  4 . 

968 

1115 

147 

4149 

10.32 

Table  VII — Selling  Price  of  Each  Lot  and  Average  Weight  and  Price  of 

Each  Steer  at  Denver, 


Lo  t  1 — 
Lot  2.... 
Lot  3,. .. 
Lot  4  — 


12  head,  13,890  lbs.  at  $5.15 
9  head,  10,080  lbs.  at  $5.15 
3  head,  2,980  lbs.  at  $4.75 
12  head,  12,600  lbs.  at  $5.00 
9  head,  9,820  lbs  at  $4.80 
3  head,  2,930  lbs.  at  $4.50 


Average 

Weight 

Average 

Price. 

per  cwt.... 

$713.29 

1157 

$59.44 

\  $5.06 . 

660.83 

1087 

55.06 

630.00 

1049 

51.66 

|  $4.72 . 

603.07 

1062 

50.25 

In  Table  VI  may  be  seen  the  average  weight  of  each  steer  in 
the  different  lots  at  the  beginning  and  close  of  the  experiment,  and 
the  average  amounts  of  the  various  kinds  of  feed  eaten  per  head 
and  the  cost  of  the  same.  This  table  should  prove  of  value  to  the 
prospective  feeder,  since  from  it  by  bearing  in  mind  that  the  figures 
represent  an  average  of  12  steers  in  each  case,  and  that  the  time 
covered  was  just  ioo  days,  it  should  be  an  easy  matter 
to  get  a  very  close  estimate  of  the  amount  of  feed  required  for  a  lot 
of  steers  for  any  stated  period;  also  the  approximate  amount  of  feed 
that  will  be  required. 

In  Table  VII  is  given  the  data  gathered  from  the  marketing 
of  the  steers.  They  were  shipped  to  Denver  and  sold  on  the  open 
market  to  the  highest  bidder.  It  is  only  fair  to  state  here  that 
none  of  the  buyers  in  the  yards  knew  anything  of  the  kinds  of  feed 
given  the  different  lots.  It  will  be  seen  that  Lots  I  and  II  sold  for 
the  same  price  with  the  exception  that  three  steers  from  Lot  II 
were  cut  back  and  were  valued  at  35  cents  per  hundred  less  than 
the  rest  of  the  lot.  All  of  the  steers  in  Lot  III  sold  for  the  same 
price,  while  of  those  in  Lot  IV,  three  were  cut  30  cents  per  hun¬ 
dred.  It  has  been  a  noteworthy  fact  through  the  entire  experiment 
that  the  steers  in  the  pulp  fed  lots  were  more  uniformly  thrifty 
than  those  that  had  no  pulp. 


IO 


STATE  AGRICULTURAL  COLLEGE. 


FINANCIAL  STATEMENT. 

Table  VIII.— Lot  I. 


11,415  lbs.  at  3c . $342.45 

23,995  lbs.  Alfalfa  at  $5.00  per  ton .  59.98 

112,117  lbs.  Pulp  at  50c  per  ton .  28.02 

7,944  lbs.  Corn  at  85c  per  cwt .  67.72 

Labor .  39.00 

Freight . 14.44 

Yardage .  3.00 

Feed  at  Stock  Yards .  8.40 


Total  cost . $563.01 

Sold  for .  715.33 


Profit . $152.32 

Profit  per  head .  12.69 


Table  IX.— Lot  II. 


11,680  lbs.  at  3c . $348.60 

37,520  lbs.  Alfalfa  at  $5  per  ton .  93.80 

7,944  lbs.  Corn  at  85c .  67.72 

Labor . 39.00 

Freight .  14.44 

Yardage .  3.00 

Feed  at  Stock  Yards .  8.40 


Total  cost 
Sold  for. . 


$574.96 

660.67 


Profit . $85.71 

Profit  per  head .  7.14 


Table  X.-Lot  III. 


11,290  lbs.  at  3c . $338.70 

26,270  lbs.  Alfalfa  at  $5  a  ton .  65.67 

116,757  lbs.  Pulp  at  50c  a  ton .  29.18 

Labor .  39.00 

Freight .  14.44 

Yardage .  3.00 

Feed  at  Stock  Yards .  8.40 


Total  cost . $498.39 

Sold  for .  630.00 


Profit .  131.61 

Profit  per  head .  10.97 


Table  XI.-Lot  IV. 


11,620  lbs.  at  3c . $348.60 

49,795  lbs.  Alfalfa  at  $5.00  a  ton .  124.48 

Labor .  39.00 

Freight .  14.40 

Yardage .  3.00 

Feed  at  Stock  Yards .  8.40 


Total  cost .  $537.88 

Sold  for .  603.07 


Profit . 

Profit  per  head 


$  65.19 
5.43 


STATE  AGRICULTURAL  COLLEGE. 


II 


Tables  8  to  1 1  inclusive  give  a  very  complete  financial  state¬ 
ment  for  each  lot  of  steers.  While  it  is  not  the  primary  object  of 
these  experiments  to  make  them  financially  successful,  yet  it  is 
gratifying  to  learn  that  in  all  cases  and  with  all  kinds  of  feed  ra¬ 
tions,  there  is  a  fair  margin  of  profit  which  is  certainly  encouraging 
to  the  general  feeder  in  Colorado. 

SUMMARY. 

Table  XII.— Giving  Data  for  an  Average  Steer  in  Each  Lot 


Lot  1. 

Lot  2. 

Lot  3. 

Lot  1. 

Weight  at  beginning  of  experiment  (lbs.) . 

951 

968 

941 

968 

Value  at  3  cents  per  pound . 

$28.53 

$29.04 

$28.23 

$29.04 

Cost  entire  p.eriod,  100  days . 

$12.95 

$13.44 

$  7.90 

$10.39 

Cost  of  feed  for  100  lbs.  gain .  ... 

$  4.60 

$  7.63 

$  4.29 

$  7.04 

Cost  of  labor  in  feeding . 

$  3.25 

$  3.25 

$  3.25 

$  8.25 

Weight  finished  steer  at  feed  lots,  (lbsj . 

1214 

1144 

1125 

1115 

Sale  weight  of  steer  at  Denver  (lbs.) . 

1157 

1088 

1050 

1062 

Shrinkage  ip  shipping  Obs.) . 

57 

56 

75 

53 

Selling  price  per  hundred  pounds . 

$  5.15 

$  5.06 

$  5.00 

$  4.73 

Value  at  selling  price  — ' . 

$59.58 

$55.05 

$52.25 

1  $50.25 

Cost  of  marketing . 

$  2.15 

$  2.15 

$  2.15 

$  2.15 

Net  profits . 

$12.70 

$  7.16 

$10.97 

$  5.44 

In  Table  XII  is  given  a  complete  summary  showing  the  aver¬ 
age  of  each  steer  in  the  various  lots.  In  thn  table  is  given  very 
complete  data  covering  the  various  points  of  comparison  in  the  re¬ 
sults  obtained  with  the  average  steer  in  each  lot. 


CONCLUSIONS. 


gam 


V  r.  An  average  “feeder”  steer  two  years  old  will  make  a 
of  1.5  lbs.  per  day  on  alfalfa  hay  alone,  and  will  require  approxi 
mately  28  lbs.  of  hay  to  make  one  pouud  of  gain. 

2.  The  addition  of  ground  corn  to  the  ration  of  alfalfa  hay 
will  increase  the  daily  gain,  increase  the  market  price  of  the  steer 
by  finishing  him  better  in  a  given  time,  and  will  add  to  the  profits 
if  the  corn  can  be  procured  below  90  cents  per  hundred  pounds. 

^  3.  A  pound  of  ground  corn  is  equal  in  feeding  value  to  2.8 

tbs.  of  alfalfa  hay  and  to  9  pounds  of  sugar  beet  pulp  for  feeding 


two-year-old  fattening  steers. 

4.  Sugar  beet  pulp  at  present  prices  is  a  cheaper  and  better 
feda  than  ground  corn  when  fed  with  alfalfa  hay  for  fattening  ma¬ 
ture  steers. 

5.  That  3.22  of  beet  pulp  is  equivalent  in  feeding  value  to 
one  pound  of  alfalfa  hay,  when  fed  in  conjunction  with  the  hay, 
giving  two-year-old  steers  all  they  will  eat  of  both  feeds. 

6.  With  alfalfa  hay  at  $5  a  ton,  it  will  pay  to  feed  a  light  ra- 


12  FEEDING  STEERS  ON  BEET  PULP,  AEFAEFA  HAY  AND  CORN. 

tion  of  ground  corn  with  the  hay,  provided  the  corn  can  be  pur¬ 
chased  at  from  85  to  90  cents  per  hundred  weight. 

7.  With  poor  alfalfa  hay  at  $5  per  ton,  sugar  beet  pulp  is 
worth  $1.50  per  ton  to  combine  with  the  hay  for  fattening  mature 
steers. 

8.  Fattening  steers  will  gain  approximately  a  pound  a  day 
more  on  a  ration  composed  of  alfalfa  hay,  ground  corn  and  beet 
pulp  than  they  will  on  a  ration  made  up  of  alfalfa  hay  and  ground 
corn  or  on  a  ration  composed  of  alfalfa  hay  and  sugar  beet  pulp, 
and  they  will  gain  almost  one  and  a  half  pounds  more  eaeh  day  on 
the  above  ration  than  when  fed  alfalfa  hay  alone. 


Bulletin  103. 


October,  1905. 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College. 


The  Thorough  Tillage  System 
for  the  Plains  of  Colorado. 


BY  W.  H.  OLIN. 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
FORT  COLLINS,  COLORADO 
1  905 


The  Agricultural  Experiment  Station. 


FORT  COLLINS,  COLORADO. 


THE  STATE  BOARD  OF  AGRICULTURE. 


Hon.  P.  F.  SHARP,  Presi dent,  - 

Hon.  HARLAN  THOMAS, . 

Hon.  JAMES  L.  CHATEJELD,  - 

Hon.  B.  U.  DYE,  ------- 

Hon.  B.  F.  ROCKAFELLOW,  -  -  -  - 

Hon.  EUGENE  H.  GRUBB,  ----- 

Hon.  A.  A.  EDWARDS,  -  -  -  - 

Hon.  R.  W.  CORWIN,  ------ 

Governor  JESSE  F.  McDONALD,  )  m  . 

President  BARTON  O,  AYLESWORTH,  \  ex-°JJlcw 


Denver, 

TERM 

EXPIRES 

1907 

Denver, 

-  1907 

Gypsum, 

19C9 

Rockyford, 

-  1909 

Canon  City, 

1911 

Carbondale, 

-  1911 

Fort  Collins, 

1913 

Pueblo, 

-  1913 

EXECUTIVE  COMMITTEE  IN  CHARGE. 

P.  F.  SHARP,  Chairman.  B.  F.  ROCKAFELLOW.  A.  A,  EDWARDS. 


STATION  STAFF. 


L.  G.  CARPENTER,  M.  S.,  Director ,  - 
C.  P.  GILLETTE,  M.  S., 

W.  P.  HEADDEN,  A.  M.,  Ph.  D., 

W.  PADDOCK.  M.  S.,  - 

W.  L.  CARLYLE,  MS.,  - 
G.  H.  GLOVER,  B.  S.,  D.  V.  M., 

R.  E.  TRIMBLE,  B.  S., 

F.  C.  ALFORD,  B.  S, 

EARL  DOUGLASS,  B.  S  ,  - 

A.  H.  DANIELSON,  B.  S., 

S.  ARTHUR  JOHNSON,  M.  S.,  - 

W.  H.  OLIN,  M.  S.,  -  -  -  - 

B.  O.  LONGYEAR,  M.  S., 

J.  A.  McLEAN,  A.  B.,  B  S.  A., 

P.  K.  BLINN,  B.  S.,  -  -  Field 


Irrigation  Engineer 

. Entomologist 

. Chemist 

-  Horticulturist 
Agriculturist 
Veterinarian 
Assistant  Irrigation  Engineer 
Assistant  Chemist 
Assistant  Chemist 
Assistant  Agriculturist 
Assistant  Entomologist 

. Agronomist 

Assistant  Horticulturist 
-  Animal  Husbandman 
Agent,  Arkansas  Valley,  Rockyford 


OFFICERS. 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S.. . Director 

A.  M.  HAWLEY,  ----------  Secretary 

MARGARET  MURRAY,  -----  Stenographer  and  Clerk 


The  Thorough  Tillage  System  for  the  Plains 

of  Colorado. 


BY  W.  H.  OLIN. 

I.  THE  PRINCIPLES  OF  SEMI-ARID  FARMING. 

Regions  having  an  annual  rainfall  of  less  than  twenty  and 
more  than  eight  inches  are  usually  considered  as  semi-aricl.  To 
successfully  grow  crops  in  such  regions  requires  a  careful  study  of 
soil  and  climatic  conditions,  with  a  selection  of  crops  as  nearly  ad¬ 
apted  to  these  conditions  as  possible.  Even  when  all  requirements  are 
seemingly  met,  a  failure  is  sometimes  the  only  result.  Experience, 
and  experiments  already  conducted  in  many  parts  of  our  nation’s 
semiarid  belt,  demonstrate  that  the  preparation  of  a  soil  reservoir  of 
good  depth  several  months  before  seeding,  the  thorough  culture  of 
this  ground  before  and  after  seeding,  the  selection  of  suitable  vari¬ 
eties  of  crops,  the  seed  of  which  is  grown  under  dry  farming  con¬ 
ditions,  are  essentials  which  very  largely  determine  success  in  farm¬ 
ing  lands  in  Colorado  where  irrigation  can  not  be  practiced. 

The  preparation  of  the  soil  reservoir  and  seed  bed  calls  for 
careful  plowing,  harrowing  and  sub-surface  packing. 

i.  Plowing. — Jethro  Tull  nearly  two  centuries  ago  said  “Til¬ 
lage  is  manure.”  Roberts’  Fertility  says  that  stirring  and  mixing 
the  soil  is  the  one  fundamental  labor  of  agriculture.  The  object  of 
plowing  should  be  to  pulverize  the  soil,  making  it  possible  to  pre¬ 
pare  a  good  seed  bed  for  the  reception  of  the  various  farm  seeds. 
The  depth  to  plow  must  depend  upon  the  time  of  plowing,  the 
character  of  the  soil  and  the  crop  to  be  grown. 

Shallow  plowing  is  preferred  for  shallow  soils  underlaid  by  an 
inferior  sub-soil  lacking  in  plant  food.  Spring  plowing  for  early 
crops  should  not  be  as  deep  as  fall  plowing  for  the  same  crops.  Ex¬ 
periments  have  shown  that  deep  plowing  of  stiff  or  clayey,  adobe 
land  in  the  spring  turns  up  unworked  or  new  soil  in  which  most  of 
the  plant  food  is  not  available,  on  account  of  the  mechanical  con¬ 
dition  of  the  ground.  Crops  on  lands  thus  plowed  often  make  an 
unfavorable  growth.  It  is  nearly  always  desirable  to  plow  sandy 
and  sandy  loam  soils  deep,  since  the  plant  food  contained  in  these 
soils  is  easily  available  and  the  deep  plowing  brings  more  plant  food 
to  the  surface  for  the  tender  young  plant  to  feed  upon,  giving  it  a 
sturdy  growth  at  the  start. 


4 


Bulletin  103. 


All  deep  plowing  is  best  done  in  the  summer  or  fall.  This 
permits  the  weathering  of  the  soil,  through  the  fall  and  winter, 
making  its  mechanical  texture  more  desirable  and  the  plant  food 
available.  Deep  plowing  assists  water  to  percolate  or  pass  through 
to  lower  depths.  Hence  it  increases  the  water  holding  capacity  of 
the  soil,  a  most  important  element  in  semi-arid  farming.  The 
deeper  the  plowing  the  greater  the  soil  reservoir.  Experiments  con¬ 
ducted  at  the  Cornell  Experiment  Station,  New  York,  by  Dr.  Rob¬ 
erts  show  that  an  acre  of  average  soil  in  good  tilth  will  hold  20  to 
25  per  cent  of  moisture  and  not  be  too  moist  for  cultivation.  It  is 
estimated  that  an  acre  of  soil  12  inches  deep  will  weigh  1,800  tons  if 
it  contains  20  per  cent  of  moisture,  1,620  tons  if  it  contains  8  per 
cent  of  moisture — the  amount  upon  which  plants  are  able  to  grow 
and  maintain  themselves.  Dr.  Roberts  says  that  an  inch  of  rainfall 
brings  to  each  acre  113  7-16  tons  of  water.  If  this  could  all  be 
retained  in  average  soil  it  would  mean  almost  7  3-5  per  cent  moist¬ 
ure,  nearly  enough  to  maintain  plant  growth.  Well  fined  soil  is 
capable  of  taking  up  two  inches  of  rainfall  in  the  first  foot  of  soil 
and  still  be  in  good  condition  to  cultivate.  Suppose  that  this  soil  is 
deeply  plowed  and  contains  1 5  per  cent  moisture ;  an  inch  or  a  two- 
inch  rain  would  find  the  soil  reservoir  able  to  hold  it.  If  this 
ground  were  shallow  plowed,  say  four  inches,  an  inch  rain  would 
saturate  the  reservoir,  while  a  two-inch  rain  would  overflow  the 
soil  reservoir,  causing  a  loss  of  water  and  severe  washing  away  of 
the  surface  soil.  Deep  plowing  therefore  increases  the  storage  ca¬ 
pacity  of  moisture  in  our  soils  from  which  the  plant  draws  as  it 
has  need. 

Good  plowing  gives  a  clean-cut. furrow  on  side  and  bottom.  It 
turns  the  inverted  furrow  slice  upon  edge  in  a  moderately  well 
pulverized  condition  with  but  few  air  spaces  at  the  bottom  edge  of 
the  furrow  slice.  A  good  coulter  lessens  draft  and  aids  in  making 
a  clean  cut  furrow.  Disking  the  ground  before  plowing  is  advant¬ 
ageous  but  increases  the  expense  of  preparing  the  seed  bed. 

A  seed  bed  from  one  to  three  inches  deep  can  be  prepared  with¬ 
out  plowing.  The  young  plants  may  grow  sturdily  at  first,  but  if  the 
soil  is  not  in  a  physical  condition  to  store  the  moisture  necessary  to 
dissolve  the  plant  food  and  render  it  available  for  the  growing  plant, 
lack  of  nourishment  will  bring  it  to  an  untimely  end  and  the  crop 
will  prove  a  failure.  Very  successful  crops  are  grown  this  way, 
when  the  moisture  is  supplied  by  ditch  or  sub-irrigation  but  it  is 
always  hazardous  to  attempt  cropping  without  thorough  tillage, 
under  semi-arid  conditions. 

A  disc  plow  will  often  leave  the  soil  in  a  good  condition  for 
the  harrow,  when  the  ground  is  too  hard  for  a  mold  board  plow  to 
do  satisfactory  work.  The  drier  the  ground  the  more  narrow 


Thorough  Tieeage  System  tor  Plains  or  Colorado.  5 


should  be  the  furrow,  whether  the  plow  be  a  mold  board  or  a  disc 
plow. 

2.  Harrowing  the  Ground. — Harrowing  is  the  process  of 
stirring  the  soil  by  some  form  of  a  toothed  or  circle  knife  imple¬ 
ment.  Its  purpose  is  the  pulverizing  of  the  soil,  reducing  it  to 
finer  tilth  than  the  plow  left  it,  filling  the  interstices  left  by  the  plow 
and  thus  leveling  the  soil.  I  believe  that  the  spike  toothed  harrow 
is  a  superior  implement  for  pulverizing  after  the  plow.  It  should 
follow  as  near  after  the  plow  as  possible  so  as  to  prevent  loss  of 
moisture  by  evaporation  from  the  newly  plowed  earth  and  the  for¬ 
mation  of  clods.  Each  half  day’s  plowing  should  be  harrowed 
that  same  half  day  in  which  it  is  plowed. 

Ground  that  is  harrowed  first  lengthwise  with  the  plowing  will 
retain  its  moisture  better,  since  it  regularly  and  evenly  fills  the  in¬ 
terstices  or  openings  at  the  bottom  edge  of  each  furrow  slice.  Al¬ 
ways  first  harrow  lengthwise  and  later  cross  harrow  if  the  ground 
is  not  in  fine  enough  tilth  for  the  seed.  Ground  that  is  inclined  to 
be  cloddy  should  be  worked  with  the  disc  harrow  instead  of  the 
spike  tooth,  double  disking  or  half  lapping  lengthwise  with  the  fur¬ 
rows.  See  that  your  disc  is  the  proper  size  to  do  the  most  effec¬ 
tive  work  in  pulverizing  the  soil.  A  fourteen  to  sixteen-inch  disc 
generally  pulverizes  better  than  an  eighteen  or  twenty-inch  disc, 
and  the  draft  is  correspondingly  greater.  Experiments  seem  to 
indicate  that  the  smaller  diameter  discs  are  better  adapted  for 
farming  conditions  on  the  Colorado  plains  than  the  larger  diameter 
discs.  Experiments  conducted  by  experiment  stations  and  by  Mr. 
H.  W.  Campbell  of  Lincoln,  Nebraska,  show  that  disking  grain 
ground  after  the  harvester  prevents  loss  of  moisture  on  stubble 
ground  through  too  rapid  evaporation,  and  prepares  the  ground  for 
the  ready  absorption  of  rain. 

3.  Sub-Sureace  Packer. — This  tool  consists  of  a  series  of 
wedge  faced  wheels  attached  to  a  common  axle.  These  wedge¬ 
faced  disks  are  18  inches  in  diameter  and  placed  vertically  on  the 
shaft  6  inches  apart.  This  machine  is  better  than  a  smooth  roller 
for  a  roller  firms  the  surface  soil  with  little  or  no  effect  upon  the 
under  or  sub-surface  soil.  The  packer  firms  the  soil  in  the  lower 
portion  of  the  furrow  slice,  restoring  the  capillariety  where  plow¬ 
ing  had  arrested  it.  This  firmed  under-surface  soil  is  enabled  to 
draw  moisture  from  below  and  give  good  normal  root  development. 
In  case  a  sub-surface  packer  is  not  obtainable,  a  corrugated  roller 
can  be  used.  It  firms  the  ground  but  not  to  the  depth  which  the 
sub-surface  packer  does.  These  packers  should  be  followed  by  a 
smoothing  harrow  to  produce  an  earth  mulch  which  shall  arrest 
capillarity  and  thereby  check  evaporation. 

A  spike  toothed  harrow  with  lever  attachments  for  regulating 


6  Bulletin  103. 

the  angle  of  the  teeth  is  a  very  satisfactory  implement  for  this 
purpose. 

4.  Summer  Curture.  Fallowing  Ground — leaving  the  land 
without  a  crop  for  one  or  more  seasons — was  a  common  practice 
with  the  ancients.  Dr.  Roberts  in  his  work  on  “Fertility  of  the 
Land/’  says  this  was  a  necessity  for  them.  The  imperfect  tools 
then  used  made  but  a  small  proportion  of  the  plant  food  in  the  soil 
available  and  the  demands  of  the  crops  grown  soon  outran  the  ob¬ 
tainable  plant  food.  Then  the  only  method  for  renewal  was  to  let 
the  soil  “weather  out”  enough  plant  food,  with  the  decayed  vege¬ 
table  matter  to  sustain  another  crop.  Some  centuries  later  the 
French  found  that  “manoeuvering”  the  land — causing  the  particles 
of  earth  to  change  place  by  tillage — made  it  more  productive.  Ex¬ 
periments  now  show  that  summer  tillage  in  our  semi-arid  lands  has 
an  added  value — it  conserves  the  moisture  while  it  renders  more 
plant  food  available.  Good  results  have  been  obtained  in  Eastern 
Washington,  Eastern  Oregon,  Utah  and  many  sections  of  Colo¬ 
rado  from  summer  culture  of  the  land  every  other  season.  It  has 
been  found  that  in  this  way  sufficient  moisture  can  be  stored  from 
the  year’s  rainfall  to  mature  a  crop,  in  many  localities. 

After  the  snows  of  winter  have  melted  in  the  spring,  plow  the 
ground  at  least  seven  to  eight  inches  deep.  Level  this  down  with 
the  harrow  and  packer,  following  this  process  with  a  smoothing 
harrow,  forming  an  earth  mulch  to  check  evaporation.  This  mulch 
should  not  be  too  fine  as  the  winds  of  the  plains  will  tend  to  rift  the 
soil,  or  blow  the  earth  mulch  entirely  away.  If  possible,  stir  the 
surface  soil  from  two  to  four  inches  every  ten  to  fifteen  days 
throughout  the  summer.  Allow  no  crust  to  form  after  summer 
showers,  as  this  will  increase  the  evaporation  of  the  soil  moisture. 
Keep  the  ground  clean — free  from  weeds. 

If  fall  grain  is  to  be  sown  it  is  advisable  to  drill  in  the  grain, 
as  this  insures  getting  it  below  the  earth  mulch  which  is  really  a 
dry  earth  blanket  used  all  summer  to  hold  the  moisture  in  the  soil 
below.  Get  the  seed  into  this  moist  under-soil  where  it  can  have 
the  moisture  so  essential  for  germination.  It  is  advisable  to  seed 
fall  grain  not  later  than  the  last  week  in  September  in  the  lower 
altitudes  and  not  later  than  the  first  week  in  September  in 
the  higher  altitudes ;  better  still,  the  third  or  last  week  in  August. 

Ground  that  has  been  well  cultivated  for  several  years  will 
produce  two  crops  in  succession  and  can  be  given  summer  culture 
the  third  year.  I11  this  way  it  is  possible  to  grow  two  crops  in  three 
years. 

If  a  farmer  expects  to  cultivate  80  acres  he  should  divide  it 
into  two  crop  divisions — cropping  40  acres  the  first  year  and  giv¬ 
ing  summer  culture  to  the  other  40  acres.  This  gives  him  a  crop 


Thorough  Tillage  System  eor  Plains  oe  Colorado.  7 

on  one  half  his  land  each  year  while  he  is  storing  up  moisture  in  the 
soil  reservoir  of  the  other  half  to  make  the  next  year’s  crop.  Farm¬ 
ers  in  the  southern  part  of  Larimer  County,  Colorado,  have  been 
able  to  raise  quite  satisfactory  wheat,  barley  and  forage  crops  by 
following  this  method  of  cropping. 

Mr.  Geo.  D.  Porter  living  at  Akron,  Colorado,  near  the  center 
of  the  plains  region  has  used  this  method  of  cropping,  for  a  small 
area,  for  several  years.  He  reported  last  fall,  when  he  seeded  his 
winter  wheat,  a  soil  reservoir  in  which  there  was  five  feet  of  moist¬ 
ure.  Last  season  gave  us  an  uuusual  amount  of  rainfall  but  this 
summer  culture  has  been  practiced  in  some  parts  of  California  for 
more  than  forty  years  with  satisfactory  results.  The  writer  knows 
of  one  section  of  California  where  it  seldom  rains  from  April  to 
September,  yet  here  some  of  the  finest  fruit  and  grain  is  grown. 
This  region  in  California  has  an  ample  supply  of  moisture  in  the 
rainy  season — the  winter  months.  This  illustration  is  simply  given 
to  show  the  value  of  the  earth  mulch  in  holding  the  moisture  which 
is  already  in  the  soil  reservoir. 

Mr.  S.  S.  Peterman  has  a  cherry  orchard  near  Fort  Collins 
that  has  never  been  irrigated.  He  depends  upon  rainfall  for  his 
moisture  in  a  region  that  averages  scarcely  fifteen  inches  per  an¬ 
num.  As  soon  in  the  spring  as  possible  he  cultivates  his  orchard 
and  continues  to  stir  the  ground  until  the  fruit  sets.  His  trees 
bear  fine  flavored  cherries  in  a  satisfactory  quantity,  while  his 
orchard  is  the  cleanest  one  in  his  neighborhood.  This  orchard  is 
eight  years  old,  but  has  not  yet  weathered  one  of  our  “dry”  years. 

Summer  culture  keeps  the  ground  in  good  tilth,  keeps  down 
weeds,  renders  the  plant  food  easily  available  for  the  next  year’s 
crop,  while  it  stores  up  the  moisture  so  necessary  to  the  plant  in 
assimilating  its  food. 

II.  SELECTION  OF  SEED  FOR  SEMI-ARID  CONDITIONS. 

Climatic  conditions  are  believed  to  have  an  influence  on  the 
development  of  certain  temperaments  and  characteristics  in  the 
breeding  of  live  stock,  although  the  hereditary  power  of  a  well-bred 
horse,  cow  or  sheep  to  transmit  its  qualities  to  its  descendents  is  the 
major  influence  and  measures  the  value  of  a  pedigree. 

While  plants,  like  live  stock,  certainly  have  strong  hereditary 
power,  yet  it  seems  true  that  climate,  soil  and  cultural  methods, 
have  an  influence  on  the  manner  of  growth  of  very  many  crops 
grown  in  our  fields. 

M.  de  Candolle,  an  eminent  plant  scientist,  has  succeeded  in 
finding  the  wild  forms  of  one  hundred  and  ninety-three  of  the 
two  hundred  and  seventy  species  of  cultivated  plants.  Of  the 
remaining  seventy-seven,  twenty-seven  he  names  as  possibly  half 


8 


Bulletin  103. 


wild  and  the  rest  he  has  so  far  failed  to  discover  in  the  wild  state. 

Darwin  in  his  investigation  of  domesticated  plants  came  to 
the  conclusion  that  in  cases  similar  to  this  the  cultivated  plant 
either  was  so  changed  in  its  growing  habit  by  its  new  environment 
that  its  wild  prototype  could  not  be  recognized  or  that  its  original 
parent  ceased  to  exist. 

Prof.  A.  M.  Ten  Eyck  of  Kansas  in  an  address  on  “Plant 
Adaptation”  before  the  Corn  Breeders’  Association  of  that  state 
last  March  stated : 

“Prom  a  single,  comparatively  valueless,  primitive  wild  form  have 
originated  in  the  course  of  time  thousands  of  valuable  varieties  of  plants, 
all  differing  from  the  original  and  some  to  such  an  extent  that  they  cannot 
be  recognized.” 

Prof.  W.  M.  Hays,  in  the  Minnesota  Experiment  Station 
Bulletin  No.  62,  speaking  of  variations  in  individual  wheat  plants 
says : 

“Among  the  four  hundred  plants  of  McKendry’s  Fife  for  example, 
plants  were  found  which  matured  in  ninety-seven  days,  others  requiring  one 
hundred  twenty-seven  days.  Among  Power’s  Fife  (wheat)  plants,  the 
range  was  from  ninety-eight  to  one  hundred  seventy-two  days;  and  among 
Haynes’  Blue  Stem  plants  the  range  was  from  ninety-nine  to  one  hundred 
twenty-eight  days. 

“The  ten  plants  which  appeared  to  the  eye  as  the  best  yielding 
plants  out  of  the  four  hundred  of  each  variety,  wrere  harvested  and  notes 
taken  as  to  the  height  of  plant,  number  of  spikes,  length  of  spikes  and  yield 
of  shelled  grain.  The  following  table  shows  the  extremes  of  the  variation  in 
each  case: 

VARIATION  AMONG  BEST  TEN  OUT  OF  FOUR  HUNDRED 

WHEAT  PLANTS. 

Name  of  Variety.  Height  of  Stalks.  Length.  No.  of  Yield  in 


inches.  of  Spikes.  Spikes.  grams, 

inches. 

Haynes’  Blue  Stem .  31  to  39  4  to  4%  19  to  31  15.4  to  19.4 

Powers’  Fife .  27  to  33  3  x/z  to  4  18  to  33  3.4  to  13.8 

McKendry’s  Fife .  30  to  33  3  V2  to  4  22  to  33  6.8  to  16.7 


In  breeding  corn,  the  writer  has  observed  that  individual  plants 
in  the  same  breed  or  type  of  corn,  vary  widely  in  producing  power, 
height  of  ears  on  the  stalk,  height  of  stalk,  width  and  number  of 
leaves  and  period  of  maturity  of  corn.  The  Iowa  Seed  Company 
state  their  earlist  maturing  type  of  dent  corn — Farmers’  Reliance — 
was  developed  by  selecting  the  lowest  ear  on  individual  plants, 
these  ears  usually  ripening  first.  At  the  Kansas  station  a  pure  bred 
type  of  corn  known  as  Reid’s  Yellow  Dent,  was  planted  in  the 
season  of  1903 — an  ear  to  a  row.  These  ears  were  carefully  se¬ 
lected  for  uniformity  and  trueness  to  the  breed  characteristics  of 
that  type  of  corn.  The  resulting  harvest  from  these  different  rows 
showed  almost  as  much  difference  in  the  character  of  plants  in  dif¬ 
ferent  rows  as  in  different  supposedly  fixed  types  of  yellow  dent 
corn,  while  difference  in  yield  between  highest  anl  lowest  was  nearly 
four  hundred  per  cent.  The  very  best  ears  from  the  best  yielding 
and  most  desirable  mother  ears  were  selected  for  the  mother  ears 


Thorough  Tillage  System  eor  Plains  oe  Colorado.  9 


of  1904  and  seeded  a  row  to  an  ear.  Marked  differences  in  growing- 
habit  were  noted,  but  differences  in  yield  from  lowest  to  highest  was 
but  a  trifle  more  than  eighty  per  cent — one  fifth  what  it  was  the 
preceding  year. 

“Selection  is  the  process  by  which  new  varieties  are  fixed.  Artificial 
crossing  may  be  used  to  induce  variation,  with  a  view  to  promote  the  de¬ 
velopment  of  new  forms,  but  selection  is  always  the  final  process  by  which 
new  varieties  are  established  and  maintained. 

“Three  principal  factors  largely  determine  the  value  of  a  variety  of 
any  cultivated  crop,  namely,  yield,  quality  and  adaptation — and  the  last 
named  is  really  the  deciding  factor  which  determines  whether  a  variety  type 
may  be  successfully  grown  in  any  locality.  In  no  two  countries,  perhaps 
in  no  two  sections  of  the  same  country  or  state,  are  the  plants  subject  to 
exactly  the  same  conditions  of  soil  and  climate.  One  section  may  have  a  dif¬ 
ferent  soil,  a  little  more  dry  weather,  and  the  plants  of  this  section  vary  to 
adapt  themselves  to  these  conditions.  If  the  plant  is  removed  from  its  na¬ 
tive  habitation  and  planted  in  a  different  part  of  the  world  or  country,  in  a 
different  soil,  surrounded  by  different  conditions  to  those  to  which  it  has 
been  accustomed,  it  is  placed  at  a  disadvantage,  it  is  exposed  to  a  new  en¬ 
vironment  to  which  it  is  not  suited.  Thus  we  can  understand  why  a  good 
variety  of  fruit  or  grain  does  not  always  give  as  good  results  in  all  places, 
and  we  should  expect  a  variety  of  plants  originating  from  the  plants  of  a 
certain  region  to  be  best  adapted  for  growing  in  that  region,  or  such  plants 
may  be  adapted  for  growing  in  any  region  having  similar  conditions  of  soil 
and  climate. 

“We  find  a  demonstration  of  this  principle  in  the  fact  that  wheat  and 
other  grains,  brought  from  the  steppes  of  Russia  and  Turkey  are  well  adapted 
for  growing  in  the  western  plains  region  of  the  United  States,  which  has  a 
climate  and  soil  very  similar  to  that  of  the  countries  named.  The  Turkey  Red 
wheat,  for  instance,  has  largely  replaced  all  other  varieties  of  winter  wheat 
grown  in  the  West,  because  of  its  greater  hardiness  and  productiveness,  and 
yet  some  of  the  varieties  which  it  has  succeeded  had  been  grown  in  the  West 
for  many  years  and  seemed  to  be  fairly  wll  adapted  to  western  climatic  and 
soil  conditions.  This  superior  hardiness  and  adaptation  which  the  Russian  and 
Turkey  varieties  of  grain  appear  to  have  in  our  western  country  may  be 
largely  credited  to  the  centuries  of  training  which  these  varieties  have  had  in 
an  environment  almost  identical  with  that  of  similar  latitudes  in  the  West, 
while  the  varieties  which  the  Russan  grans  succeeded  as  a  rule  have  been 
those  which  have  been  gradually  moved  from  the  Eastern  and  Middle  states 
farther  west,  and  although  many  of  these  varieties  have  gradually  become 
more  or  less  hardy  and  fairly  well  adapted  for  growing  in  our  western  cli¬ 
mate,  yet,  in  the  comparatively  short  period  during  which  they  have  been 
grown  under  western  conditions,  apparently  they  have  not  become  so  hardy 
and  well  adapted  to  those  conditions  as  the  Russian  and  Turkey  varieties.” 
(Prof.  Ten  Eyck’s  Plant  Adaptation.) 

For  more  than  ten  years  Mr.  Robert  Gauss  of  Denver,  has 
been  growing  a  certain  type  of  wheat,  under  drouth  conditions  with 
results  that  are  in  accord  with  statements  made  by  Prof.  Ten  Eyck. 
Each  year  Mr.  Gauss  has  made  his  seed  selections  looking  toward 
the  seeding  of  wheat  for  the  plains,  that  has  good  drouth  resisting 
qualities. 

This  past  season  the  writer  seeded  some  of  this  wheat,  in  May, 
on  the  very  driest  seed  bed  which  he  has  ever  used.  It  was  sown 
broadcast,  and  seed  covered  with  a  spike  toothed  harrow.  The 
seeding  was  done  on  an  experimental  plat  located  on  the  C.  F.  & 
I.  grounds  five  miles  southwest  of  Pueblo,  Colorado.  This  wheat 


IO 


Bulletin  103. 


matured  when  barley  and  oats,  seeded  at  the  same  time,  in  the  same 
seed  bed,  perished  from  lack  of  moisture.  Mr.  Gauss  tells  me  he 
can  trace  this  wheat  as  a  drouth  resistant  wheat  for  at  least  eigh¬ 
teen  years ;  while  his  wheat  has  not  been  tested  for  milling  qualities, 
his  results  would  indicate  the  value  of  selecting  seed  grown  under 
semi-arid  conditions,  for  semi-arid  farming.  Persons  coming  from 
a  lower  altitude  with  a  moist  climate,  often  are  completely  pros¬ 
trated  on  being  transported  to  Leadville — Colorado’s  “Cloud  City,” 
nearly  two  miles  above  sea  level. 

In  a  similar  manner,  but  probably  not  to  so  marked  a  degree, 
altitude  and  climate  affect  our  crops  and  we  should  try  to  secure 
acclimated  seed  or  at  least  obtain  seed  from  regions  with  similar 
climatic  and  soil  conditions.  Seed  corn  from  the  Mississippi  river 
states  cannot  be  expected  to  make  a  sturdy  growth  in  eastern  Colo¬ 
rado  ;  seed  wheat  from  near  tide  water  cannot  be  expected  to  make 
a  quick,  rapid  growth  at  an  altitude  of  8,000  to  10,000  feet. 

Colorado  farmers  find  grain  of  good  quality  grown  and  de¬ 
veloped  in  the  region  of  their  farms  gives  best  results  and  Colorado 
grown  seed  should  be  so  selected  that  it  shall  take  precedence  of 
all  other  seed  on  our  home  markets. 

Mr.  A.  H.  Danielson,  Asst.  Agronomist,  a  few  years  ago  de¬ 
cided  to  test  selection  for  hardiness  in  winter  wheat.  For  this 
test  he  selected  a  number  of  varieties.  The  ones  which  showed  the 
best  quality  grain  and  gave  the  best  yields  he  used  as  the  basis  for 
his  work.  The  first  year  all  were  badly  winter  killed.  From  the 
plants  which  lived  through  and  matured  grain,  he  obtained  seed 
and  so  continued  for  four  years.  This  year  all  of  his  plots  showed 
a  perfect  stand,  while  other  plots  not  thus  treated  showed  from 
twenty  to  thirty  per  cent  winter  killed. 

The  value  of  good  vital  seed  is  shown  in  an  experi¬ 
ment  conducted  by  Professor  R.  A.  Moore  of  the  Wisconsin 
Experiment  Station  with  oats.  He  selected  from  two  pecks 
of  seed  oats  sent  to  him  by  the  U.  S.  Department  of  Agri¬ 
culture,  33  especiallly  fine,  large,  plump  kernels  and  planted  them  in 
a  choice  plot  by  themselves  in  1899.  From  these  plants  he  re¬ 
ceived  sufficient  seed  to  plant  a  good  sized  bed.  The  next  year  he 
began  sending  out  seed  to  members  of  the  Wisconsin  Experimental 
Union,  asking  that  a  record  of  harvest  and  sales  be  kept  so  he 
could  trace  the  progeny  of  his  33  oat  kernels;  last  year  (1904,)  he 
found  the  harvest  of  the  oats  with  a  pedigree  tracing  back  to  the 
33  kernels  of  1899,  numbered  500,000  bushels.  Hardiness,  quality 
and  productiveness  are  to  be  sought  for  in  our  field  crops  if  we 
would  farm  profitably  in  any  region.  Because  of  the  struggle  for 
existence  in  our  semi-arid  fields,  our  farm  seeds  should  be  chosen 
with  great  care  and  with  these  three  essentials  always  in  mind. 


Thorough  Tillage  System  eor  Trains  oe  Colorado,  ii 


Rate  of  Seeding. — Because  of  the  limited  amount  of  moisture 
in  the  soil  a  limited  amount  of  seed  should  be  used  in  seeding  all 
crops  grown  on  semi-arid  lands  which  can  not  be  irrigated.  If 
seeded  too  heavily  there  is  not  sufficient  moisture  in  the  soil  to  ma¬ 
ture  all  plants  and  the  entire  crop  in  a  very  dry  year  is  liable  to 
“fire” — ripen  prematurely.  It  is  better  to  under  seed  rather  than 
over  seed.  The  rate  of  seeding  depends  so  much  upon  the  size  of 
seed,  mechanical  condition  of  the  seed  bed,  method  of  seeding  and 
moisture — conditions  that  it  is  impossible  to  give  the  exact  amount 
of  seed  which  should  be  used  in  seeding  the  various  field  crops. 
The  writer  this  past  season  carried  on  a  co-operative  experiment 
with  a  farmer  testing  two  varieties  of  drouth  resistant  wheats  on 
sod.  One  was  seeded  nearly  twice  as  heavy  as  the  other  one,  yet 
the  field  having  the  lightest  seeding  had  equally  as  good  a  stand  as 
the  field  seeded  the  heavier,  because  there  were  nearly  twice  as  many 
kernels  in  a  bushel  and  each  kernel  made  a  plant.  Below  is  a  sug¬ 
gestive  table  which  may  prove  helpful  to  persons  who  are  seeding 
crops  for  the  first  time  on  semi-arid  lands.  The  amount  of  seed 
required  is  usually  from  one  half  to  two  thirds  that  which  is  used 
for  the  irrigated  lands. 


RATE  OF  SEEDING  FOR  NON-IRRIGATED  LANDS. 


Name. 

Lbs.  per  Bushel. 

Lbs. 

per  l 

GRAIN  CROPS. 

Wheat  . 

. 60 

45 

to 

60 

Barley . 

. 48 

50 

to 

60 

Oats . 

. 32 

40 

to 

60 

Rye . 

. 56 

35 

to 

50 

Emmer,  or  Speltz.  .  .  . 

. 40 

45 

to 

60 

Field  Corn  (in  hills)  .  . 

.  (shelled)  ...  56 

4 

to 

6 

Field  Corn  (in  drills  or  lister  rows). 

5 

to 

7 

Sweet  Corn  (in  hills)  . 

6 

to 

8 

Sweet  Corn  (in  drills) 

10 

to 

15 

Kafir  Corn . 

. 56 

4 

to 

5 

Broom  Corn . 

. 46  to  55 

2 

to 

4 

Field  Peas . 

. 60 

30 

to 

50 

Field  Beans . 

. 60 

15 

to 

25 

Proso  . 

. 60 

6 

to 

12 

Millett  . 

. 60 

5 

to 

10 

Buckwheat . 

. 50 

20 

to 

30 

Flax . 

. 56 

20 

to 

30 

FORAGE  CROPS: 

Sorghum  or  Cane . 5  0 

Alfalfa . 60 

Meadow  Fescue . 24 

Brome  Grasses . 14 


Vetches . 

ROOT  CROPS: 

Sugar  Beets  .  . 
Mangel  Wurzel 

Carrots . 

Stock  Turnips 


8  to  2  5  (varies  with 
method  of  seeding.) 
20  to  25 
15  to  25 
15  to  25 
20  to  30 

10  to  15 
8  to  12 
3  to  5 

iy2  to  4  (manner  of 
seeding.) 


12 


BuivIylyTiN  IO3. 


III.  CROPS  FOR  THE  SEMI-ARID  LANDS. 

The  amount  of  water  required  by  growing  crops  is  shown  by 
experiments  to  vary  with  the  soil,  climatic  conditions  and  the  nature 
of  the  crop  grown.  Crops  having  a  large  percentage  of  water  in 
their  composition  will  necessarily  require  more  moisture  to  produce 
a  healthy,  vigorous  growth  than  crops  with  a  low  percentage  of 
moisture  in  their  composition. 

Experiments  to  determine  the  best  grain,  forage  and  root  crops 
for  drouth  resistant  power  and  productiveness  are  now  being  con¬ 
ducted  at  the  experiment  stations  in  the  semi-arid  states.  Conclu¬ 
sive  results  have  not  yet  been  obtained  but  the  following  crops 
are  worthy  of  consideration  for  semi-arid  farming.  All  of  these 
have  been  successfully  grown  in  some  portion  of  the  semi-arid 
West,  but  probably  none  of  these  crops  would  do  well  in  all  regions 
of  Colorado  where  semi-arid  farming  is  being  practiced. 

I.  GRAIN  CROPS. 

1.  Corn — Early  maturing  types  of  dent  and  flint  varieties  are 
chosen.  Cool  nights,  high  altitudes  and  short  summers  are  not 
adapted  to  this  cereal  since  corn  is  a  semi-tropical  plant.  When  the 
seed  bed  is  well  prepared  and  the  crop  thoroughly  tilled,  eastern 
Colorado  farmers  have  been  able  to  obtain  from  10  to  25  bushels 
per  acre  with  the  average  season. 

Favorable  seasons  a  greater  yield  is  reported  in  a  few  indi¬ 
vidual  cases.  In  raising  corn  in  Colorado  it  is  highly  important  to 
grow  an  acclimated  variety.  Obtain  seed  grown  as  nearly  as  pos¬ 
sible  under  the  same  climatic  conditions  which  prevail  in  the  region 
where  you  wish  to  plant  it.  Select  seed  of  good  vital  power.  It  is 
especially  important  in  all  semi-arid  regions  to  give  the  crops  a  good 
start,  for  they  usually  have  a  hard  struggle  for  existence,  even 
under  the  thorough  tillage  system  of  farming.  Hence  the  use  of 
good,  strong,  vital  seed  grown  under  drouth  resistant  conditions 
is  very  important. 

2.  Kafir  Corn.  This  is  an  important  crop  both  for  grain  and 
forage.  It  is  a  non-saccharine  sorghum.  The  seed  is  borne  in  a  head 
at  the  top  of  the  stalk  and  seems  to  be  relished  by  all  classes  of  stock. 
In  tests  conducted  at  the  Kansas  Experiment  Station  the  feeding 
value  of  Kafir  corn  for  fattening  hogs  was  found  to  be  90  per  cent 
of  the  feeding  value  of  corn  (Kans.  Bulletin  No.  128).  This  crop 
may  appear  almost  dried  up,  favorable  conditions  return  and  it 
revives  in  a  remarkably  short  space  of  time.  It  seems  to  withstand 
dry  and  windy  periods  to  a  remarkable  degree,  if  these  periods  do 
not  last  too  long. 

The  Fort  Hays  Sub-Station  in  Kansas,  gives  the  following 
plan  of  seeding  for  grain  and  for  forage: 


Thorough  Tillage  System  eor  Plains  oe  Colorado.  13 


“Kafir  corn  grown  for  seed  does  best  when  planted  with  a  lister  in 
rows  from  3  to  3  Vz  feet  apart,  and  cultivated  enough  to  about  level  the 
ridges.  If  seed  alone  is  desired,  a  special  plate  should  be  used  in  the  drill 
that  will  put  a  stalk  every  4  to  6  inches  apart.  If  the  fodder  is  also  sought, 
the  seed  should  be  much  thicker.  A  common  practice  is  to  use  the  regular 
corn  plate  set  to  drop  12  to  16  inches  apart.  This  will  drop  a  dozen  or  more 
grains  at  a  place.  When  planted  in  rows  the  corn  harvester  should  be  used 
for  cutting  the  crop,  and  the  bundles  set  up  in  good  sized  shocks.  When  the 
heads  are  dry  they  may  be  threshed  with  the  ordinary  thresher.  The  most 
satisfactory  method  of  harvesting  the  heads  is  to  take  a  low  wagon  with  a 
tight  rack  and  a  good  sized  chunk  laid  across  the  back  end,  with  two  stakes 
set  in  it,  about  six  inches  apart  at  the  bottom  and  one  foot  at  the  top,  18 
inches  from  the  chunk.  One  man  with  a  heavy  broadax  stands  on  the  wagon 
and  chops  the  heads  off,  as  two  or  three  others  pick  up  the  bundles  and  lay 
them  on  the  chunk. 

“With  two  wagons  and  five  men  this  is  a  very  rapid  way  of  obtaining 
seed  The  bundles  may  easily  be  reshocked  or  laid  in  piles.  The  threshing 
of  the  entire  stalk  is  not  satisfactory,  if  the  stalks  are  of  any  size.  It  is  very 
hard  on  a  machine,  and  the  fodder  does  not  keep  so  welPwhen  cut  up.  It 
also  dries  out,  which  is  undesirabble.  The  practice  would  be  similar  to  cut¬ 
ting  bread  for  the  table  a  month  or  so  beforehand.  It  is  not  palatable. 

“For  roughage  alone,  the  general  practice  is  to  plant  with  the  grain 
drill  at  the  rate  of  a  half  to  a  bushel  per  acre,  depending  upon  the  land. 
This  is  cut  with  a  mowing  machine,  raked,  and  put  in  large  cocks.  A  great 
deal  of  labor  can  be  saved  by  using  a  buck-rake  or  “go-devil,”  to  bunch  the 
windrows.” 

The  White  Kafir  with  a  black  hull  or  chaff  is  the  earliest  va¬ 
riety  and  so  far  seems  to  be  the  hardiest  grower  and  best  yielding 
variety. 

3.  Wheat.  (A)  Spring  Wheat. — The  best  spring  wheat 
variety  for  semi-arid  conditions  seems  to  be  a  durum  wheat  known  as 
Kubanka  durum — U.  S.  Cerealist,  M.  A.  Carleton,  introduced  some 
15  variety  types  of  durum  from  a  part  of  Russia  with  soil  and 
climatic  conditions  quite  similar  to  eastern  Colorado.  The  type 
which  seems  best  adapted  to  Colorado  conditions  is  the  Kubanka 
durum.  This  is  a  spring  wheat  in  our  latitude  and  should  be  seeded 
as  early  in  the  spring  as  ground  and  weather  conditions  will  permit. 

The  durum  wheat,  having  been  grown  for  many  generations  in 
a  semi-arid  climate  in  Russia,  withstands  drouth  conditions  better 
than  our  common  spring  wheats.  It  must  be  remembered,  however, 
that  no  wheat  can  be  matured  without  some  moisture.  Kubanka 
durum  has  good  drouth  resistant  power,  but  one  must  not  expect 
this  wheat  to  mature  a  satisfactory  crop  without  several  inches  of 
rainfall  during  the  growing  season.  While  durum  wheat  has  been 
tested  this  past  season  in  thirty  counties  in  Colorado,  experiments 
have  not  been  conducted  long  enough  to  tell  us  the  minimum 
amount  of  moisture  required  to  produce  a  crop  under  our  differing 
conditions  of  soil  and  climate. 

This  wheat  has  the  heaviest  and  coarsest  beards  found  on  any 
wheat.  The  kernel  is  very  hard  and  most  millers  feel  that  this 
wheat  requires  special  machinery  for  milling.  For  this  reason 
but  few  local  millers  in  the  state  are  buying  durum  wheat.  Mr. 


H 


Bulletin  103. 


B.  F.  Hottel  of  the  Lindell  Mills,  Fort  Collins,  Colorado,  ground 
1,500  bushels  of  Kubanka  durum  last  fall.  He  put  up  five  pound 
sample  sacks  of  this  flour  and  the  Agronomy  Department  assisted 
in  placing  these  sacks  in  more  than  fifty  families  to  be  tested  in 
both  light  bread  and  biscuits.  The  reports  sent  in  from  this  test 
showed  that  light  bread  or  biscuits  made  from  Mr.  Hottel’s  durum 
flour  compared  very  favorably  with  the  patent  flour  in  common 
use,  in  texture,  elasticity  (lightness),  flavor  and  moisture.  While 
the  bread  was  possibly  a  shade  darker  it  was  not  considered  a  seri¬ 
ous  objection.  Comparative  tests  made  later,  by  the  Domestic 
Science  Department,  Mrs.  A.  M.  Hawley  and  Mrs.  Winnie  E. 
Olin,  confirmed  the  previous  tests,  showing  the  Hottel  durum  flour 
made  a  very  satisfactory  bread.  This  wheat  is  also  used  in  making 
semolina,  a  milled  product  from  which  our  very  best  French  and 
Italian  macaroni  is  made.  A  milling  firm  in  Cincinnati,  Ohio,  is 
now  making  from  8,000  to  9,000  pounds  of  macaroni  per  day  from 
western  grown  durum  wheat.  This  wheat  when  first  introduced, 
was  known  as  macaroni  wheat  and  it  was  believed  that  it  could  not 
be  used  for  anything  else.  The  milling  and  baking  tests  conducted 
in  North  and  South  Dakota,  Minnesota  and  Colorado,  demonstrate 
that  durum  or  macaroni  wheat  gives  a  desirable  flour  for  bread  or 
pastry.  Prof.  J.  H.  Shepard,  Chemist  of  the  South  Dakota  Station, 
has  found  that  the  importation  of  wheat  known  as  Kubanka  No. 
5639,  gives  the  best  quality  flour  of  all  durum  wheats. 

This  wheat  should  not  be  sown  on  the  irrigated  lands,  as  the 
use  of  too  much  water  produces  starchy  kernels,  causing  the  wheat 
to  deteriorate  in  quality.  It  should  not  take  the  place  of  any  bread 
wheat  now  being  successfully  grown  in  any  region.  It  is  recom¬ 
mended  as  a  spring  wheat  on  lands  where  other  spring  wheat  does 
not  yield  a  satisfactory  crop,  in  a  region  where  there  is  sufficient 
rainfall  to  mature  a  drouth  resistant  wheat,  giving  the  farmer  a 
semi-arid  bread-wheat.  Like  all  new  crops,  a  market  must  be  de¬ 
veloped  for  it. 

This  wheat  has  only  been  grown  in  our  state  a  few  years  and 
farmers  are  urged  to  study  market  conditions  and  determine  their 
acreage  of  this  new  crop  by  the  market  demands  for  this  wheat. 

( B )  Winter  Wheat. — The  variety  of  wheat  has  given  the 
most  satisfactory  yields  and  shown  drouth  resistant  power  is 
Turkey  Red.  This  wheat  has  been  grown  quite  successfully  in 
Kansas,  Nebraska  and  portions  of  Colorado  for  many  seasons.  It 
is  the  wheat  which  made  Kansas  the  greatest  winter  wheat  state 
in  the  Union  and  is  as  good  for  the  irrigated  as  for  the  semi-arid 
lands.  The  millers  of  Colorado  prefer  this  to  any  other  wheat  for 
flour  production.  It  has  a  ready  and  constant  market  at  any  mill 
in  the  state.  Seed  for  semi-arid  lands  should  be  obtained  from 


Thorough  Tiuuage  System  for  Prains  oe  Colorado.  15 

regions  where  this  seed  has  been  kept  pure  and  grown  “above  ditch.” 

The  sub-stations  in  Nebraska  and  Kansas  located  in  the  west¬ 
ern  portions  of  these  states  can  aid  our  eastern  Colorado  farmers 
to  obtain  seed  and  the  Monticello  sub-station  farm  in  Utah  will 
help  our  western  Colorado  farmers  to  obtain  seed  wheat,  while  the 
writer  will  also  assist  anyone  desiring  this  wheat,  to  obtain  as  good 
seed  as  possible,  grown  under  drouth  resistant  conditions. 

Any  winter  wheat  which  has  good  milling  quality  and  shows 
drouth  resisting  power,  adapted  to  the  region  where  grown,  can 
and  should  be  developed  by  wise  seed  selection  and  careful  culture 
treatment. 

All  semi-arid  wheat  should  be  harrowed  or  run  over  with  a 
weeder  to  break  up  the  crust  which  may  form,  and  thus  check  too 
rapid  evaporation.  Wheat  can  thus  be  advantageously  cultivated 
until  it  is  knee  high.  Often  seeding  rows  sixteen  instead  of  eight 
inches  apart  (stop  up  every  other  hole  in  the  drill)  is  advantageous. 
Then  one  can  use  a  beet  cultivator  or  other  small  toothed  cultivator 
and  cultivate  the  crop,  keeping  the  ground  well  stirred. 

Cultivating  grain  in  the  semi-arid  region  lessens  evaporation 
and  thereby  holds  more  moisture  for  the  growing  crop. 

4.  Barley. — This  grain  has  not  been  generally  sown  as  a 
drouth  resisting  crop.  Bald  barleys  can  be  grown  in  the  higher 
altitudes  and  in  the  northern  and  north  central  portions  of  the 
state,  with  a  fair  degree  of  success.  Bald  barley  when  ripe  has  a 
very  hard  kernel  and  most  feeders  find  it  best  to  crush  or  grind  it 
before  feeding  to  stock.  Cut  in  the  soft  dough  or  before  ripening, 
it  is  fed  in  the  straw  without  threshing.  A  bearded  feed  barley  is 
grown  in  some  sections  of  the  state.  Obtain  seed  grown  on  non- 
irrigated  lands. 

5.  Emmer.  This  grain  belongs  to  the  wheat  group  and  is 
sometimes  called  speltz  by  our  farmers.  Both  emmer  and  speltz 
have  a  hull  which  clings  to  the  kernel  and  does  not  come  off  when 
threshed. 

Speltz  and  emmer  differ  in  size  of  head  and  arrangement  of 
spiklets  on  the  spike  or  head.  Emmer  is  the  more  preferable  grain 
of  the  two  for  our  conditions.  This  is  a  spring  grain  and  should 
be  seeded  the  same  as  barley.  It  is  used  as  a  feed  grain  for  nearly 
all  kinds  of  stock.  It  is  being  grown  more  extensively  in  the 
South  Platte  and  on  The  Divide  east  of  Colorado  Springs,  than  in 
any  other  portion  of  the  state. 

6.  Oats.  This  grain  is  not  well  adapted  for  non-irrigated 
lands.  Only  the  earlier  maturing  types  should  be  grown.  It  is 
often  sown  for  a  hay  crop  in  eastern  Colorado  and  in  higher  alti¬ 
tudes  above  the  ditches. 


i6 


Bulletin  103. 


7.  Rye.  Winter  rye  or  early  varieties  of  spring  rye  are  sown, 
for  hay  and  for  grain  crops  as  well.  Choose  a  market  type  of  rye 
and  seed  a  small  acreage  at  first. 

II.  EORAGE  CROPS. 

1.  Cane  or  Sorghum.  This  is  grown  for  feed  to  supplement 
the  range  in  winter.  Grow  early  maturing  types.  Drilled  sorghum 
is  a  more  certain  crop  than  when  sown  broadcast. 

2.  Proso.  This  is  a  drouth  resistant  millet,  imported  within 
recent  years  by  the  U.  S.  Cerealist,  Prof.  M.  A.  Carleton,  from  the 
driest  regions  of  Europe.  This  crop  grows  a  wealth  of  seed  in  a 
close  panicled  head,  while  it  affords  considerable  forage  in  its  broad 
leaved  foliage.  It  is  a  spring  crop,  but  should  not  be  seeded  until  all 
danger  of  frost  is  passed.  There  are  several  varieties  but  the  white 
proso  furnishes  the  most  foliage  and  fully  as  much  grain  as  any 
other  type  of  proso. 

3.  Millet.  Mr.  J.  E.  Payne  in  Bulletin  No.  77  of  this  station, 
reports  this  as  a  widely  grown  crop  with  a  yield  varying  from  one 
quarter  to  one  half  a  ton,  according  to  season  and  locality.  The 
German  millet  has  proven  one  of  the  more  desirable  types  to  grow 
on  account  of  its  yield  of  grain. 

4.  Alfalfa.  This  crop  is  being  tested  in  many  parts  of  our 
semi-arid  land.  Results  differ  with  methods  of  seeding,  soil  and 
the  seasons.  Experiments  already  conducted  are  not  convincing. 
This  is  our  most  important  perennial  forage  crop  and  the  writer 
would  ask  that  the  following  suggestions,  given  in  Bulletin  No.  90, 
by  Mr.  J.  E.  Payne,  be  noted  by  all  who  contemplate  seeding  alfalfa 
on  non-irrigated  land :  “The  important  factor  in  getting  a  stand 
of  alfalfa  is*  getting  a  good  seed  bed  for  it.  My  experience  has 
taught  me  to  plow  the  ground  early  in  the  season  five  to  eight  inches 
deep,  harrow  until  it  is  thoroughly  packed  and  then  wait  until  the 
ground  is  thoroughly  wet  before  planting  the  seed.  If  this  occurs 
before  the  middle  of  July  go  on  the  ground  with  a  light  drag  har¬ 
row  as  soon  after  the  rain  as  the  surface  appears  to  be  dry  and  break 
the  crust  thoroughly. ”  Then  sow  the  seed  with  a  press  drill  and 
follow  with  the  harrow.  A  good  stand  has  been  obtained  every  time 
I  have  followed  this  rule.  “Some  have  been  successful  with  the 
hoe  drill  and  some  have  used  the  press  drill.  One  man  seeded  his 
alfalfa  with  a  lister,  taking  off  the  shares  and  running  the  seed  in 
behind  the  subsoiler  part  of  the  machine.  The  time  to  sow  alfalfa 
may  be  any  time  when  the  ground  is  in  good  condition,  between  the 
1st  of  May  and  the  1st  of  July.  Having  a  stand  of  alfalfa,  the 
next  question  is  how  shall  it  be  maintained  against  its  enemies,  the 
drought  and  the  grasshoppers?  It  has  been  demonstrated  in  west- 


EFFECT  OF  GOOD  AND  POOR  SOIL  PREPARATION. 


tv*  •••'  :  - 

||W^Y 


Thorough  Tillage  System  for  Plains  of  Colorado.  17 

ern  Kansas  that  thoroughly  discing  the  old  alfalfa  field  usually  in¬ 
creases  the  yield  of  hay,  while  it  also  prevents  the  deposit  of  grass¬ 
hopper  eggs  in  the  field.” 

Mr.  H.  T.  Miller  on  a  ranch  near  Fort  Collins,  has  some  ten 
acres  of  alfalfa  above  the  ditch  that  has  been  seeded  down  twenty- 
.  eight  years.  He  cuts  two  crops,  and  favorable  years,  like  1904  and 
1905,  he  cuts  three  crops  each  year.  This  is  located  on  the  lower 
level  and  some  years  receives  considerable  moisture,  which  runs  off 
from  the  higher  ground  surrounding  the  field. 

Many  of  these  “favorable  locations,”  can  be  successfully  found 
in  many  parts  of  eastern  and  western  Colorado,  where  irrigation 
can  not  be  practiced. 

5.  Bronte  Grass.  There  are  several  varieties  of  this  grass  but 
the  one  that  has  been  the  most  widely  tested  in  Colorado  is  Bromus 
inermis.  This  was  first  tested  on  the  experimental  grounds  of  the 
California  station,  being  imported  by  Prof.  Hilgard  from  Europe 
and  offered  for  distribution  to  California  farmers  in  1884.  This 
grass  has  proven  to  be  one  of  our  best  drouth  resistant  grasses  in 
Colorado.  If  requires  a  good  seed  bed  and  a  reasonable  amount 
of  moisture  for  germination  and  early  growth.  It  is  one  of  the 
first  grasses  to  appear  in  the  spring  and  the  last  grass  to  die  down 
in  the  fall. 

6.  Meadow  Fescue.  This  is  a  grass  resembling  our  blue  grass 
in  habit  of  growth,  but  carries  a  heavier  sward.  It  is  English  blue 
grass  and  where  seed  can  be  obtained  from  non-irrigated  land  has 
made  a  reasonably  good  growth  in  western  Kansas  and  Nebraska. 
It  is  of  slow  growth  the  first  season,  has  a  metallic  green  lustre  and 
is  better  adapted  for  a  pasture  than  a  meadow  grass. 

7.  Field  Peas.  This  crop  under  ditch  and  sub-irrigation  has 
made  an  excellent  growth  in  many  parts  of  our  state.  But  few 
tests  have  been  made  on  non-irrigated  lands.  These  indicate  that 
field  peas  can  not  be  counted  as  a  sure  crop  every  season,  but  very 
often  seeding  early  in  the  spring,  peas  will  mature  sufficiently  for 
a  good  hay  crop.  Peas  for  hay  can  be  cut  with  a  mower,  and  well 
cured  hay  makes  good  feed  for  cattle  and  sheep.  It  is  not  advisable 
to  feed  this  hay  to  horses. 


>111.  ROOT  CROPS. 

Potatoes,  sugar  beets  and  rutabagas  have  been  grown  on  non- 
irrigated  lands  in  a  few  sections  of  the  state.  Root  crops  need 
considerable  moisture  and  it  will  require  experiments  for  several 
seasons  to  determine  to  what  extent  these  crops  can  be  grown  on 
semi-arid  lands  in  the  various  sections  of  our  state. 


i8 


Bulletin  103. 


IV.  NATIVE  PASTURES  AND  MEADOWS. 

Colorado  has  some  most  nutritious  native  grasses.  While  the 
grass  is  short  and  sparse  in  many  parts  of  our  ranges,  when  not 
overstocked,  it  keeps  the  stock  in  excellent  condition. 

The  hay  made  from  native  grass  commands  a  premium  in  the 
market.  Much  of  our  very  best  quality  hay  grows  above  the  irri¬ 
gation  ditches.  One  of  our  most  hardy  and  best  native  hay  grasses 
is  the  Western  Wheat  Grass  (Agropyrum  occidentale),  known  lo¬ 
cally  as  Colorado  Blue  Stem.  This  is  a  leafy  grass,  forms  an  even 
sod,  and  experiments  show  it  can  be  sown  the  same  as  brome  grass 
or  meadow  fescue,  with  good  success. 

A  farmer  near  Fort  Collins  sowed  three  acres  of  Blue  Stem 
with  a  nurse  crop  this  spring,  and  has  a  good  stand  of  grass  on 
cultivated  ground.  He  sold  the  Blue  Stem  hay  from  a  native  grass 
meadow  for  five  to  six  dollars  a  ton  more  than  he  could  have  ob¬ 
tained  for  his  alfalfa  hay.  His  native  hay  is  always  of  good  quality 
and  sells  from  $12  to  $16  per  ton  in  the  market. 

Native  meadows  may  be  made  profitable  when  good  native 
hay  grasses  are  carefully  chosen.  The  underground  stems  of  many 
of  these  grasses  give  them  good  drouth  resisting  power  and  causes 
them  to  thicken  rapidly,  making  finer  and  therefore  superior  quality 
hay,  yielding  from  one  and  one  half  to  two  and  one  half  tons  per 
acre.  Many  arroyas  or  lower  level  areas  furnish  favorable  locations 
for  Blue  Stem  meadows. 

The  writer  will  be  glad  to  assist  anyone  who  wishes  to  start 
a  Blue  Stem  or  Grama  Grass  meadow. 

IV.  PRINCIPLE  OF  CAPILLARITY. 

Water  in  the  soil  used  in  the  plant  economy  is  known  as  capil¬ 
lary  water.  The  water  found  in  the  bottom  of  postholes  dug  in  the 
wet  ground  or  standing  on  the  surface  of  the  ground  is  called 
ground  water  or  free  water.  This  free  water  flows 
under  the  force  of  gravity,  as  does  the  water  in  our  irrigation 
ditches.  When  the  ground  becomes  thoroughly  saturated  all  the 
spaces  between  the  grains  of  soil  become  filled  with  water.  This 
cuts  off  all  air  from  plants  and  they  drown  or  suffocate. 

Ground  or  free  water  is  not  in  that  particular  form  available 
to  the  plant.  When  it  sinks  into  the  soil  and  later  comes  up  in  small 
quantities  in  the  capillary  tubes  of  the  soil,  it  is  the  essential  capil¬ 
lary  water  which  aids  in  dissolving  plant  food  in  the  soil  so  the 
root  hairs  can  utilize  said  food.  Plants  get  all  the  water  they  use 
through  their  roots.  When  the  texture  of  the  soil  is  just  right  and 
the  amount  of  moisture  ample,  the  soil  grains  and  granules  will  be 
surrounded  by  this  water  as  a  thin  sheet  or  film.  This  is  continuous 


Thorough  Tillage  System  eor  Plains  oe  Colorado.  19 

where  the  grains  or  granules  are  in  contact  or  nearly  so  and  seeks 
to  extend  in.  all  directions.  If  a  dish  be  filled  with  soil  composed  of 
grains  and  this  soil  be  rounded  up  into  a  cone,  one  can  get  some 
conception  of  this  capillary  action  of  the  water  in  the  soils  of  our 
fields. 

Pour  water  slowly  into  the  dish  and  it  will  be  observed  that 
soon  this  water  is  drawn  quite  a  distance  upward  from  the  base  of 
the  cone,  as  shown  in  diagram.  Place  two  rectangular  pieces  of 
window  glass  in  a  basin  of  water  so  that  two  edges  of  the  glass 
plates  touch.  It  will  be  observed  that  where  the  edges  are  in  con¬ 
tact  with  each  other  is  where  the  water  rises  higher  than  anywhere 
else  on  the  plates. 


COLO.  AG.  EXPT.  6TA. 

FIGURE  4. 

(From  First  Book  of  Farming.) 

a.  Saturated  soil-water  drawn  up  by  capillary  action  from  bottom  of 

basin. 

b.  Dry  soil. 


FIGURE  5. 

a-b.  Water  line  between  glass  pfates. 


This  action  is  also  clearly  shown  by  the  diagram  used  by  many 
text  books  in  physics.  Place  several  glass  tubes  varying  in  size 
from  a  quarter  of  an  inch  in  diameter  to  as  small  a  tube  as  you 
can  obtain,  with  one  end  of  each  tube  in  a  basin  of  water.  It  will 


20 


Bulletin  103. 


be  noticed  that  the  water  on  the  sides  of  the  tubes  is  above  the 
height  of  the  water  in  the  basin  and  the  smaller  the  tube  the  higher 
will  be  the  water  on  the  sides  of  the  tube. 

“The  force  which  causes  the  water  to  rise  in  these  tubes  is 
called  capillary  force,  from  an  old  Latin  word  capillum,  (a  hair), 
because  it  is  most  marked  in  hairlike  tubes,  the  smaller  the  tube  the 
higher  the  water  will  rise.  The  water  which  rises  in  the  tube  is 
called  ‘capillary  water.”’  (Goodrich’s  First  Book  of  Farming). 

This  book  of  Mr.  C.  L.  Goodrich  (formerly  instructor  in  Agri¬ 
culture  in  Agricultural  Institute,  Hampton,  Va.,)  shows  that,  for 
their  best  development  and  growth,  roots  of  plants  must  have  a 
firm,  mellow  soil,  a  ventilated  soil,  a  warm  soil,  a  soil  supplied  with 
plant  food  and  a  moist  soil.  The  following  interesting  diagram 
teaches  the  relative  amounts  of  film  moisture  held  by  coarse  and 
fine  soils.  Here  are  two  tumblers,  one  with  a  half  pound  of  coarse 
soil,  the  other  with  a  half  pound  of  fine,  sandy  loam.  In  a  small 
phial  is  shown  the  amount  of  water  necessary  to  cover  each  half 
pound  with  a  film  of  moisture.  It  requires  more  than  five  times  as 
much  water  for  the  sand  as  it  does  for  the  coarse  soil. 


A.  B  CD. 

COLO.  AG.  £XPT.  5TA. 

FIGURE  6. 


A.  Coarse  soil. 

B.  Phial  containing  amount  of  water  necessary  to  cover  the  coarse 
soil  with  a  thin  film  of  moisture. 

C.  Phial  containing  the  amount  of  water  necessary  to  cover  the  fine 
sandy  loam  with  a  thin  film  of  moisture. 

D.  Fine  sandy  loam. 

This  shows  that  fining  the  soil  increases  the  capillarity  of  the 
soil,  its  power  to  hold  capillary  water. 

It  has  been  estimated  by  careful  agriculturists  that  the  film 
surface  of  a  cubic  foot  of  clay  loam  spread  out  would  cover  three- 
fourths  of  an  acre.  When  these  capillary  tubes  of  the  soil  extend 
to  the  surface  the  hot  sun  of  our  semi-arid  lands  pumps  the  water 
from  them  which  is  seemingly  wasted  in  the  dry  air  of  these  regions. 
The  earth  mulch  is  the  dry  blanket  which  breaks  capillary  con¬ 
nection  between  the  under  surface  soil  tubes  and  the  hot  outer  sur- 


Thorough  Tillage:  Syste:m  lor  Plains  or  Colorado.  21 


face,  checking  this  seriously  rapid  evaporation.  Of  course  the 
finer  the  mulch  the  more  perfect  its  action.  W ere  it  not  for  the  winds 
on  our  plains,  we  could  make  a  dust  mulch  and  thus  get  the  most 
perfect  earth  mulch  for  checking  evaporation  of  moisture  from  the 
soil.  The  danger  from  wind  blowing  soil  and  seed  from  the  field 
is  too  great  and  farmers  are  cautioned  not  to  make  the  earth  mulch 
too  due.  Leave  the  soil  as  loose  as  possible  on  top,  so  as  to  prevent 
this  capillary  action  reaching  to  the  surface,  but  do  not  make  it 
of  dust-like  fineness. 

The  blanket-like  action  of  this  earth  mulch  and  the  difficulty 
the  water  has  in  getting  through  it,  is  well  illustrated  by  loaf  sugar 
and  granulated  sugar.  Place  one  of  these  hard  squares  of  loaf 
sugar  in  a  teaspoon  and  lower  it  so  it  is  partly  submerged  in  a 
cup  of  coffee.  How  soon  it  is  saturated.  Place  the  same  amount 
of  granulated  sugar  in  the  teaspoon  and  lower  as  before  in  the 
coffee  and  observe  how  much  longer  it  takes  to  saturate  the  finely 
ground  sugar  than  it  did  the  loaf  sugar.  The  finer  flour  sugar 
used  by  confectioners  takes  still  longer  for  water  to  saturate  it.  A 
thoroughly  fine,  dry,  dust  blanket  requires  more  moisture  to  wet 
through  it,  to  the  soil  you  want  to  reach  with  moisture,  since  the 
dust  is  so  much  finer  and  has  therefore  a  greater  film  surface  than 
the  under  soil.  On  the  other  hand,  when  moisture  seeks  to  come 
up,  it  has  the  same  difficulty  to  get  to  the  surface  of  the  dust  blanket 
and  be  lost  in  the  hot,  dry  air  above,  which  it  experiences  in  getting 
down. 

For  this  reason  our  earth  mulch  should  be  kept  as  fine  as  the 
action  of  prevailing  winds  will  permit. 

Remember,  capillary  force  will  carry  down  as  well  as  up,  and 
we  can  deepen  the  root  growing  power  of  our  farm  crops  by  deep 
plowing  and  summer  culture,  which  stores  and  conserves  soil 
moisture. 

V.  EXPERIMENTS  AND  EXPERIENCE  IN  SEMI-ARID 

FARMING  IN  OTHER  STATES. 

The  following  questions  were  sent  to  the  experiment  stations 
in  each  of  the  western  states  in  the  semi-arid  regions,  where  crops 
are  being  grown  without  irrigation. 

QUESTIONS. 

1.  To  what  extent  is  semi-arid  farming-,  without  irrigation,  practiced 
in  your  State. 

2.  With  what  success? 

3.  Do  your  best  farmers  under  this  system  of  farming  try  to  obtain 
a  crop  each  year  from  a  given  field,  or  only  every  other  year? 

4.  Will  you  tell  me  what  preparation  you  think  makes  the  most  sat¬ 
isfactory  seed  bed  for  semi-arid  farming  conditions? 

5.  What  is  your  average  rainfall  in  localities  where  semi-arid  farm¬ 
ing  is  practiced? 


22 


Bulletin  103. 


6.  How  do  your  farmers  conserve  this  moisture? 

7.  What  tools  are  used  in  doing  this  work? 

8.  What  crops  have  proven  most  successful  for  you? 

9.  What  yields  are  obtained? 

10.  What  literature  can  you  cite  me  to  for  information  on  the 
thorough  tillage  system  of  farming  under  semi-arid  conditions? 

The  answers  received  from  these  questions  show  that  semi- 
arid  farming,  where  irrigation  cannot  be  practiced,  is  now  being 
carried  on  with  some  degree  of  success  in  eastern  Washington  and 
certain  portions  of  Oregon,  Idaho,  Montana,  Wyoming,  Cali¬ 
fornia,  Nevada,  Utah,  Colorado  and  New  Mexico. 

The  reply  letter  from  Prof.  E.  E.  Elliott,  Agriculturist  at  the 
Washington  Experiment  Station,  located  at  Pullman,  Washington, 
gives  us  the  farm  system  which  eastern  Washington  farmers  have 
followed  for  several  seasons  quite  successfully. 

Pullman,  Washington,  June  14,  1905. 

Dear  Sir: 

Replying  to  the  questions  in  your  letter  of  June  8th,  I  will  make  the 
following  answers:  (1.)  One-third  of  the  State  of  Washington  is  available 
for  dry  farming  and  a  very  large  part  of  it  is  now  under  cultivation.  In 
using  the  word  “dry  farming,”  I  refer  to  agricultural  operations  outside  of 
irrigation.  (2).  This  part  of  Washington  is  by  far  the  most  fertile  and  pro¬ 
duces  the  largest  crops  in  the  State  except  those  under  irrigation.  It  is 
largely  devoted  to  the  culture  of  the  different  grains  and  embraces  the  fa¬ 
mous  wheat  region  of  eastern  Washington.  (3.)  It  is  the  general  practice 
to  summer  fallow  for  fall  grain,  a  crop  being  produced  by  this  means  every 
other  year.  Many  of  our  progressive  farmers  are  trying  to  introduce  other 
crops  to  take  the  place  of  the  summer  fallow  in  the  alternate  years.  (4.) 
Probably  the  best  preparation  of  the  ground  under  the  summer  fallow  sys¬ 
tem  is  to  plow  it  in  June  and  cultivate  thoroughly  throughout  the  season. 
By  this  means  the  moisture  is  conserved  and  the  seeding  can  begin  much 
earlier  in  the  fall.  (5.)  The  average  rain  fall  throughout  the  semi-arid 
regions  of  this  State  where  farming  is  practiced,  runs  from  12  to  23  inches. 
You  will  understand,  however,  that  through  part  of  this  region  the  condi¬ 
tions  for  conserving  this  moisture  are  very  favorable,  owing  to  the  nature  of 
the  soil.  Successful  crops  of  grain  are  being  produced  where  the  rain  fall 
is  as  low  as  ten  inches.  Since  much  of  our  wheat  is  grown  from  fall  sown 
crop  and  the  greater  amount  of  the  moisture  is  precipitated  during  the 
winter  and  spring  months,  there  is  little  difficulty  in  conserving  a  sufficient 
amount  of  the  moisture  to  produce  a  crop,  and  it  is  rare  that  a  failure  oc¬ 
curs  from  the  lack  of  moisture.  (7.)  The  tools  employed  for  cultivating 
the  plowed  ground  are  the  common  harrow  used  everywhere,  although 
specially  designed  tools  intended  to  destroy  wild  oats  are  coming  into  gen¬ 
eral  use.  (8.)  This  question  is  answered  by  question  one.  (9.)  The 
yields  of  wheat  range  from  20  to  50  bushels.  Oats,  from  50 
to  90,  and  barley  slightly  less,  while  rye  is  grown  almost  entirely  for  hay  and 
that  in  the  extremely  dry  sections.  (10.)  I  regret  that  we  have  no  liter¬ 
ature  that  would  be  of  much  service  to  you  on  this  subject. 

Thanking  you  for  this  inquiry,  I  am, 

Very  truly  yours, 

E.  E.  ELLIOTT. 

Mr.  F.  M.  Gum  and  Mr.  W.  L.  Putnam,  special  students  in 
Agronomy  for  spring  term  of  1905,  assisted  me  in  preparing  these 
questions  and  carrying  on  the  correspondence.  The  replies  which 
they  received  are  hereby  acknowledged : 

Prof.  J.  H.  Shepperd,  Dean  of  Agriculture,  North  Dakota. 


Thorough  Tillage  System  eor  Plains  oe  Colorado.  23 


Prof.  F.  B.  Linfield,  Director  State  Experiment  Station,  Montana. 

Prof.  B.  C.  Buffum,  Professor  of  Agriculture,  State  University,  Wyo. 

Prof.  Luther  Foster,  Director  Experiment  Station,  New  Mexico. 

Prof.  Lewis  A. ,  Merrill,  Agronomist,  Utah  Experiment  Station. 

Prof.  T.  L.  Lyon,  Agriculturist,  Nebraska  Experiment  Station. 

Prof.  A.  M.  Ten  Eyck,  Agriculturist,  Kansas  Experiment  Station. 

Prof.  Jas.  Withycombe,  Oregon  Experiment  Station. 

Prof.  G.  A.  Crosthwait,  Idaho  Experiment  Station. 

Prof.  M.  A.  Carleton,  United  States  Cerealist,  Department  of  Agricul¬ 
ture,  Washington,  D.  C. 

These  answers  show  that  summer  culture  is  being  practiced 
with  considerable  success.  This  plan  contemplates  making  the 
soil  a  reservoir  to  hold  sufficient  moisture  to  grow  a  crop  every 
other  year.  The  rain  fall  in  those  portions  of  the  western 
states  where  this  system  of  farming  is  practiced  varies  from  10  to 
25  inches.  Successful  crops  are  being  produced  in  both  Utah  and 
eastern  Washington  with  the  average  rainfall  near  the  minimum. 
It  must  be  remembered  that  soil  as  well  as  climatic  conditions  quite 
largely  determine  the  success  of  any  system  of  farming. 

Director  Linfield  of  the  Montana  Experiment  Station  says : 

“In  certain  sections  of  this  State  farming  without  irrigation  is  prac¬ 
ticed  quite  extensively.  This  is  particularly  the  case  in  Gallatin  Valley,  where 
from  75,000  to  100,000  acres  are  farmed  in  this  way.  Probably  a  larger 
area  than  this  is  farmed  near  Great  Falls  and  in  the  Flathead  country  around 
Kalispell.  There  is  also  quite  a  large  area  cropped  without  irrigation  in  other 
sections  and  very  successfully  indeed.  We  are  at  present  trying  to  encour¬ 
age  the  extension  of  this  method  of  farming  in  other  parts  of  the  State.  Con¬ 
ditions  look  very  favorable  in  the  Bitter  Root  Valley,  in  the  Judith  Basin, 
and  in  the  higher  districts  back  from  the  Yellowstone  river,  both  north 
and  south.  In  the  drier  portions  of  the  State  the  practice  is  to  crop  the 
land  every  second  year  only.  In  the  Gallatin  Valley  this  is  particularly  the 
case,  fall  wheat  and  fall  rye  being  the  crops.  Around  Great  Falls  and  Flat- 
head  spring  crops  are  grown  and  the  cropping  is  usually  every  year.  It  will 
depend  of  course  to  a  certain  extent  upon  the  rainfall  and  climatic  condi¬ 
tions  which  vary  considerably  in  the  different  valleys  of  the  State. 

“We  have  not  experimented  long  enough  to  determine  just  exactly 
what  preparation  of  the  ground  makes  the  best  seed  bed  for  dry  land  farm¬ 
ing  conditions.  I  am  inclined  to  think  that  with  many  of  our  farmers  their 
practice  is  not  the  best.  Where  crops  are  grown  every  year,  the  land  must  be 
plowed  in  the  fall  and  plowed  deep,  then  cultivated  in  the  spring  just  as  early 
as  possible  or  as  soon  as  the  land  gets  dry  enough  to  work.  This  working 
is  continued  until  the  weather  is  warm  enough  to  sow  the  crop.  The  time 
of  sowing  varies  from  the  latter  part  of  March  to  the  first  of  May,  depending, 
of  course,  on  the  climatic  conditions  in  the  lower  and  higher  valleys.  For 
fall  crops,  the  land  is  usually  plowed  in  the  spring  and  then  worked  down 
immediately  with  the  disc  and  drag  harrow,  and  cultivated  frequently  during 
the  summer  to  conserve  the  moisture  and  then  fall  wheat  is  sown  usually 
about  the  first  week  in  September.  Some  sow  the  latter  part  of  August. 
Some  do  not  sow  until  the  early  part  of  October,  but  the  earlier  sowing 
gives  the  best  results  as  a  rule.  The  average  rainfall  in  our  best  dry  farm 
districts  is  about  16  to  18  inches,  varying  of  course  with  the  different  years. 
In  this  State  no  special  tools  have  been  introduced  for  the  work  of  culti¬ 
vating.  The  disc  and  spring  tooth  harrow  and  the  drag  harrow  are  the 
only  tools  used  in  the  cultivation  of  the  ground. 

“In  the  Gallatin  Valley,  fall  wheat  and  fall  rye  are  the  principal  crops 
grown  on  the  land.  Around  Great  Falls  spring  crops  are  more  generally 
grown,  wheat,  early  oats,  bald  barley,  and  spring  rye.  Timothy  hay  and 


24 


Bulletin  103. 


brome  grass  are  also  grown  to  a  considerable  extent,  particularly  the  former, 
and  alfalfa  is  being  tried  with  considerable  success.  It  seems  to  do  well 
once  it  is  well  started  in  the  ground.  In  the  Flathead  country  also,  spring 
crops  are  grown,  but  here  the  clover  seems  to  do  a  little  better  than  the  al¬ 
falfa,  although  it  is  not  a  permanent  crop.  In  the  Gallatin  Valley  the  fall 
wheat  will  usually  yield  from  20  to  25  bushels  per  acre  on  the  average  and  I 
believe  around  Great  Falls  somewhat  similar  crops  are  obtained  as  the  con¬ 
ditions  are  a  little  more  favorable.” 

Prof.  A.  M.  Ten  Eyck  of  Kansas,  in  speaking  of  the  tools  used 
for  preparing  the  seed  bed  in  western  Kansas,  says : 

“Disk  plows  are  being  commonly  used  now  in  western  Kansas.  They 
appear  to  be  better  adapted  for  plowing  dry,  hard  land,  than  the  moldboard 
plows.  Other  tools  used  are  the  disk  harrow,  common  harrow  and  some 
make  use  of  a  sub-surface  packer,  or  corrugated  roller.” 

Prof.  James  Withcombe  of  the  Oregon  Experiment  Stations, 

says : 

“Replying  to  your  letter  of  the  7th,  beg  to  say  we  have  no  specific  date 
as  to  wheat  growing  under  semi-arid  conditions  without  irrigation,  in  this 
State.  There  are,  however,  several  million  bushels  of  wheat  grown  annually 
under  practically  arid  conditions  and  without  irrigation. 

“Precipitation  in  several  of  our  wheat  growing  counties  will  range  from 
8  to  14  inches  annually  and  the  wheat  crop  in  these  sections  will  range 
from  15  to  35  or  even  4  0  bushels  per  acre,  some  seasons. 

“The  prevailing  system  is  to  summer  fallow  every  alternating  year;  in 
this  way  some  of  the  moisture  of  the  preceding  year  is  conserved  for  the 
wheat  crop.  There  is  no  especial  system  of  culture  developed  and  ordinary 
agricultural  implements  are  used,  such  as  gang  plows  of  the  ordinary  mould 
board  pattern,  and  the  disk  plow  is  used.  The  better  class  of  farmers  en¬ 
deavor  to  work  their  ground  down  well  immediately  after  plowing;  in  this 
way  the  furrow  slice  is  thoroughly  pulverized  and  made  compact,  and  in  this 
condition  it  conserves  the  maximum  amount  of  capillary  moisture. 

“The  soil  in  these  sections  is  in  excellent  physical  condition,  being 
largely  volcanic  ash  with  considerable  organic  matter.  However,  the  pres¬ 
ent  system  of  farming  is  very  injurious  and  in  time  will  doubtless  develop 
very  unsatisfactory  conditions  for  wheat  production.  While  from  8  to  12 
inches  of  precipitation  may  be  sufficient  to  produce  a  good  crop  of  wheat 
now,  later  when  the  organic  matter  becomes  reduced,  a  great  deal  more 
moisture  will  be  required  as  the  soil  will  be  less  capable  of  retaining  moisture. 

“Trusting  this  supplies  the  desired  information  and  if  we  can  be  of 
further  assistance  at  any  time,  you  will  kindly  advise  us.” 

VI.  AMOUNT  OF  MOISTURE  REQUIRED  BY 

FARM  CROPS. 

The  amount  of  moisture  required  by  the  various  farm  crops 
varies  with  the  character  of  the  crop  and  the  climatic  conditions 
under  which  they  are  grown.  The  experiments  already  carried  on 
in  the  agricultural  stations  of  Europe,  and  the  Eastern  and  Central 
States,  east  of  the  Mississippi  river  in  the  United  States,  show  that 
the  leading  grain  and  root  crops  require  from  271  to  576  pounds  of 
water  to  produce  one  pound  of  dry  matter  under  normal  conditions, 
in  a  normal  season. 

Hellriegel  of  Germany  and  Prof.  F.  H.  King  of  Wisconsin, 
give  the  amount  of  water  to  produce  one  pound  of  leading  crops  as 
follows : 


Thorough  Tillage  System  eor  Plains  oe  Colorado.  25 


Wheat  .  .  . 
Barley  .  .  . 

Oats  . 

Corn  . 

Clover  .  .  . 
Field  Peas 
Potatoes  . 


453  lbs.  water. 

464.1  ” 

503.9  ” 

270.9  ” 

576.6  ” 

477.2  ” 

385.1  ” 


The  Utah  Experiment  Station  has  found  that  under  semi-arid 
conditions  the  evaporation  is  such  that  wheat  requires  750  pounds 
to  mature  one  pound  of  dry  matter. 

Counting  the  weight  of  straw  necessary  to  grow  1  bushel  of 
wheat  (60  lbs.)  as  90  lbs.  (1  1-2  times  the  weight  of  grain),  we 
find  that  it  requires  56  1-4  tons  of  water  to  produce  one  bushel  of 
wheat  in  our  climate.  The  moisture  required  to  mature  a  crop  of 
wheat  is  believed  to  indicate  the  maximum  amount  required  by 
most  any  farm  crop  in  the  semi-arid  lands  of  Colorado. 


VII.  ANNUAL  RAINFALL  FOR  COLORADO. 

The  U.  S.  Weather  Bureau  has  divided  the  state  into  weather 
districts  for  convenience  in  making  and  recording  reports.  The 
average  annual  and  crop  season  rainfall  in  these  several  districts  is 
indicated  on  the  chart  given  below.  These  averages  are- made  from 
the  government  reports  and  cover  the  period  observations  have  been 
made.  The  minimum  is  six  and  the  maximum  thirty-seven  years. 
Through  the  courtesy  of  Mr.  F.  H.  Brandenburg,  District  Fore¬ 
caster  for  the  Rocky  Mountain  District,  we  are  enabled  to  give  this 
valuable  data  on  the  rainfall  by  districts. 


figure  7. 

a.  Average  annual  moisture  precipitation. 

b.  Average  precipitation  February  to  August. 

Weather  districts  are  marked  by  full  lines  and  county  limits  by  dotted 
lines  on  the  chart. 


26 


Bulletin  103. 


Station  normals,  with  the  number  of  years  weather  records 
have  been  taken,  are  as  follows : 

I — NORTH  CENTRAL  DISTRICT. 


Average  Annual. 

No.  Years.  Precipitation  Normal. 


1. 

Alford  . 

10 

17.75 

inches. 

2. 

Boulder . 

9 

17.20 

9  9 

3. 

Boxelder . 

13 

17.14 

99 

4. 

Denver  . 

33 

14.49 

99 

5. 

Fort  Collins . 

25 

14.47 

99 

6. 

Greeley . 

14 

11.76 

99 

7. 

Laporte  . 

14 

14.97 

99 

8. 

Waterdale  . 

10 

15.47 

99 

District  Normal . 

Crop  Season,  Normal  for  Dis- 

16 

15.41 

99 

trict,  February  to  August. 

11.81 

99 

II — EASTERN  DISTRICT. 


1. 

Cheyenne  Wells  . 

11 

15.64 

inches 

2. 

Fort  Morgan . 

9 

11.53 

99 

3. 

Fox  . 

13 

16.65 

9  9 

4. 

Grover  . 

8 

11.29 

99 

5. 

Holyoke  . 

9 

15.96 

9  9 

6. 

Le  Roy . 

16 

15.30 

99 

7. 

Wallet  . 

10 

18.11 

99 

8. 

Wray . 

12 

17.30 

9  9 

9. 

Yuma  . 

14 

17.05 

99 

10. 

Seibert  . 

10 

15.21 

99 

District  Normal . 

Crop  Season,  Normal  for  Dis- 

11 

15.41 

9  9 

trict,  February  to  August. 

12.66 

99  • 

Ill — ARKANSAS- 

-PLATTE  DIVIDE. 

1. 

Castle  Rock . 

13 

17.74 

inches 

2. 

Colorado  Springs  . 

25 

14.32 

9  9 

3. 

Glen  Eyrie . 

13 

15.35 

9  9 

4. 

Haups  (Hugo  P.  O.) . 

12 

13.76 

99 

5. 

Husted  . 

17 

15.98 

9  9 

District  Normal . 

Crop  Season  Normal  for  Dis- 

16 

15.37 

9  9 

trict,  Feb.  to  August  .... 

12.56 

99 

IV — ARKANSAS  VALLEY  AND 

BACA  CO. 

1. 

Canon  City . 

15 

12.33 

inches 

2. 

Holly . 

9 

15.16 

9  9 

3. 

Lamar  . 

14 

15.57 

99 

4. 

Las  Animas . 

37 

11.33 

99 

5. 

Pueblo  . 

17 

12.11 

9  9 

6. 

Rocky  Ford . 

15 

12.86 

99 

7. 

Blaine . 

14 

15.89 

99 

8. 

Vilas  . 

14 

14.01 

99 

District  Normal . 

Crop  Season  Normal  for  Dis- 

17 

13.53 

99 

trict,  Feb.  to  Aug . 

10.67 

99 

Thorough  Tillage:  System  for  Plains  of  Colorado.  27 


V — SOUTH  CENTRAL  DISTRICT. 

Average  Annual. 

No.  Years.  Precipitation  Normal. 


1. 

Hoehne . 

14 

13.15 

inches 

2. 

Trinidad . 

10 

17.10 

99 

3. 

Westcliffe . 

11 

17.41 

99 

District  Normal . 

Crop  Season  Normal  for  Dis- 

12 

15.89 

99 

trict,  Feb.  to  Aug . 

11.24 

9  9 

VI— 

-SAN  LUIS  VALLEY. 

1. 

Garnett . 

12 

6.38 

inches 

2. 

Saguache  . 

14 

7.22 

9  9 

3. 

San  Luis . 

14 

11.78 

99 

4. 

Fort  Garland . 

25 

12.74 

99 

District  Normal . 

Crop  Season  Normal  for 

Dis- 

16 

9.53 

99 

trict,  Feb.  to  Aug.  .  . 

6.81 

99 

VII — SOUTHWESTERN  DISTRICT. 

1. 

Durango  . 

12 

16.04 

inches 

2. 

Mancos . 

6 

13.72 

9  9 

3. 

Hermosa  . 

7 

14.30 

99 

District  Normal . 

Crop  Season  Normal  for  Dis- 

8 

14.69 

9  9 

trict,  Feb.  to  Aug . 

8.58 

9  9 

VIII — GRAND  AND 

UNCOMPAHGRE 

VALLEYS. 

1. 

Cedaredge  . 

12 

10.93 

inches 

2. 

Collbran  . 

12 

13.65 

99 

3. 

Delta . 

14 

8.04 

9  9 

4. 

Fruita . 

6 

8.77 

99 

5. 

Grand  Junction . 

17 

8.50 

99 

6. 

Grand  Valley . 

13 

11.20 

9  9 

7. 

Montrose . 

10 

9.11 

9  9 

8. 

Paonia . 

10 

9.62 

99 

9. 

Silt . 

10 

12.04 

99 

District  Normal . 

12 

10.21 

99 

Crop  Season  Normal  for  Dis 

trict,  Feb.  to  Aug . 

7.89 

99 

IX — NORTHWESTERN  DISTRICT. 

1. 

Lay . 

12 

12.13 

inches 

2. 

Meeker . 

13 

15.66 

99 

3. 

Pagoda  . 

14 

18.76 

99 

4. 

Rangeley . 

8 

8.39 

99 

District  Normal . 

12 

13.74 

9  9 

Crop  Season  Normal  for  Dis- 

trict,  Feb.  to  Aug . 

8.44 

99 

RAINFALL  BY  MONTHS  AT  THE  AGRICULTURAL  COLLEGE,  FORT  COLLINS,  COLORADO. 


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Thorough  Tiuuagr  System  ror  Puains  or  Colorado.  29 

It  is  to  be  observed  that  the  weather  station  records  have  not 
been  taken  for  the  same  length  of  time  in  the  different  districts  nor 
for  the  same  number  of  years  at  the  various  stations  within  the 
districts. 

The  above  record  is  just  as  the  U.  S.  Weather  Office  has  re¬ 
ceived  it  and  indicates  the  number  of  years  the  different  stations 
have  reported  observations.  It  may  possibly  be  interesting,  in  this 
connection,  to  look  over  the  rainfall  by  months  and  years,  as  re¬ 
corded  by  Mr.  R.  E.  Trimble,  in  charge  of  the  meteorological  ob¬ 
servations  at  the  Fort  Collins  Station,  in  the  North  Central  District 
of  the  state: 

It  will  be  seen  by  this  table  that  the  years  1873,  1888  and  1893 
had  less  than  10  inches  and  the  year  1901  more  than  20  inches  of 
rainfall.  The  last  ten  years  show  an  average  of  15.95  inches,  while 
the  preceding  years,  for  which  there  is  full  record,  give  an  average 
of  but  12.12  inches  rainfall.  This  would  seem  to  suggest  that  our 
rainfall  has  great  variations.  It  was  the  exceptionally  dry  years  of 
1873,  1888  and  1893  which  gave  the  farmers  on  our  eastern  plains 
little  or  no  harvest. 

It  is  these  “dry”  years  which  test  all  systems  of  crop  farming 
and  soil  culture.  The  past  few  years  have  been  quite  favorable  for 
any  system  of  careful  farming,  but  we  need  to  profit  by  the  ex¬ 
periences  of  the  past  and  not  rely  too  much  upon  the  average  rain¬ 
fall  or  even  the  rainfall  for  some  several  years  back.  It  is  those 
years  with  a  minimum  rainfall  which  test  our  systems  of  crop 
farming.  We  have  not  met  these  years  very  successfully  in  the  past 
and  the  careful  plains’  farmer  will  be  conservative  in  his  farming 
ventures,  until  he  has  successfully  tided  over  one  or  more  of  the 
“dry”  years,  when  the  rainfall  drops  below  10  inches  per  annum. 


Conclusions 


1.  Do  not  assume  that  all  unoccupied  land  is  good  farming  land 
under  any  system  o  f  soil -culture  or  crop  farming. 

2.  Character  of  soil,  amount  of  rainfall,  method  of  farming  and 
market  conditions,  on  land  where  irrigation  can  not  he  practiced,  must  largely 
determine  the  success  or  failure  in  all  farming  ventures  in  Colorado. 

3.  Methods  of  farming  which  (a)  conserve  the  soil  moisture,  (b)  pre¬ 
pare  a  good  seed  bed,  (c)  reduce  the  evaporation  to  as  near  the  minimum 
as  possible,  (d)  use  good  vital,  acclimated  seed,  (e)  employ  a  crop  rotation 
which  has  stock  foods  prominent,  contain  at  least  one  money  crop,  (f)  and 
the  practice  of  thorough  tillage  of  the  ground,  often  tide  the  farmer  over  bad 
years  and  insure  his  success  in  good  years. 

4.  With  all  these  conditions  met,  crop  failures  or  low  prices  will 
prove  disastrous  some  years,  unless  stock  raising  is  combined  with  crop 
farming. 

5.  Most  of  the  crop  should  be  “driven  to  market,”  in  the  stock  sold 
from  the  farm. 

6.  Natural  conditions  must  be  considered  in  determining  whether 
lands  can  be  made  more  profitable  for  farming  than  for  grazing  purposes. 

7.  The  first  principles  of  semi-arid  farming  was  enunciated  by  the 
English  farmer,  Jethro  Tull,  nearly  three  centuries  ago,  who  said  “Tillage 
is  manure.” 

8.  Present  day  experiences  and  experiments  demonstrate  that  fining 
the  soil  has  a  tendency  to  render  more  plant  food  available. 

9.  All  so-called  soil  culture  systems,  are  groupings  of  few  or  many 
of  the  principles  of  the  thorough  tillage  system,  which  is  the  correlated  ex¬ 
perience  of  our  best  farmers  of  past  and  present  time. 

10.  The  Thorough  Tillage  System  of  farming  considers: 

(a) .  Time  and  manner  of  plowing  the  ground. 

(b) .  Time  and  manner  of  harrowing. 

(c) .  Firming  the  soil  and  formation  of  an  earth  mulch  to  arrest 

evaporation  in  semi-arid  regions. 

(d) .  Summer  culture  to  fine  the  soil,  conserve  moisture  and  pre¬ 

pare  a  good  seed  bed  for  any  crop  under  drouth  conditions. 

(e) .  Principle  of  capillarity  and  how  moisture  may  be  conserved. 

(f) .  Selection  of  seed  and  rate  of  seeding. 

(g) .  Crops  which  have  shown  drouth  resistant  power. 

(h) .  Amount  of  moisture  required  by  plants. 

(i) .  Average  crop  season  rainfall  for  a  period  of  years  in  lo¬ 

cality  where  farming  is  to  be  practiced. 

(j) .  Crop  rotations  most  profitable  for  the  farmer  and  the  land. 

11.  Small  grain,  forage  crops  and  potatoes  have  been  successfully 
grown  on  the  Colorado  Divide  and  in  certain  sections  of  eastern  Colorado, 
without  irrigation.  Thorough  tillage  will  undoubtedly  increase  the  areas 
where  these  crops  can  be  successfully  grown  in  our  semi-arid  lands. 

12.  Our  best  native  grass — Western  Wheat  Grass,  (Colorado  Blue 
Stem) — Prof.  R.  A.  Oakley  of  the  Agrostology  Division  of  the  Department  of 
Agriculture,  Washington,  D.  C.,  finds  will  do  best  on  irrigated  ground  with 
one  early  irrigation.  More  water  is  a  detriment.  This  would  indicate  we 
may  yet  be  able  to  induce  this  grass  to  make  a  profitable  hay  crop  on  culti¬ 
vated  lands  where  we  have  ten  or  more  inches  of  rainfall  per  annum. 


Thorough  Tillage  System  ror  Plains  or  Colorado.  31 


13.  Roots  of  all  cultivated  plants  make  their  best  growth  when  the 
following  conditions  are  supplied: 


soil  well  supplied  with  plant  food. 


14.  The  earth  mulch  prevents  excessive  evaporation  and  thus  con¬ 
serves  moisture. 

15.  Deep  plowing  furnishes  a  soil  reservoir  of  good  depth  to  store 
moisture  and  summer  culture  conserves  it. 

16.  Crops  require  more  moisture  to  mature  them  under  semi-arid 
than  under  humid  conditions. 

17.  Our  field  crops  rank  from  the  lowest  to  highest  in  amount  of 
moisture  required  to  mature  them  as  follows:  Corn,  potatoes,  wheat,  barley, 
field  peas,  oats,  alfalfa  and  red  clover. 

18.  Ten  inches  of  rain  furnishes  enough  moisture  to  mature  more 
than  twice  that  number  of  bushels  of  wheat  per  acre. 

19.  The  amount  of  rainfall,  together  with  the  selection  of  drouth 
resistant  crops,  must  be  considered  under  any  system  of  soil  culture — under 
semi-arid  conditions. 

20.  The  total  area  of  land  which  can  be  successfully  farmed  within 
Colorado’s  semi-arid  belt  is  yet  to  be  determined.. 


Index 


Page. 

Alfalfa  . 16 

Amount  of  Moisture  Required  by  Farm .  24 

Annual  Rainfall  for  Colorado . 25 

Barley  .  15 

Brome  Grass  .  17 

Capillarity,  Principles  of .  18 

Conclusions  .  30 

Corn  . 12 

Crops  for  Semi-arid  Lands .  12 

Development  of  Drouth  Resistant  Power .  9 

Durum  Wheat  .  13 

Earth  Mulch  .  6 

Emmer  .  15 

Experiments  and  Experience  in  Semi-arid  Farming  in  Other  States .  21 

Factors  to  be  Considered  in  a  Variety  of  Crop  to  Grow .  9 

Field  Peas  .  17 

Harrowing,  Manner  of  .  5 

Harrowing,  Purpose  of  .  5 

Harrowing,  Time  of  .  5 

Kafir  Corn  .  3 

Meadow  Fescue  .  1 

Millet  .  16 

Moisture  Capacity  of  Plowed  Land .  5 

Native  Meadows  .  18 

Oats  .  15 

Plowing,  Manner  of . 3-4 

Plowing,  Object  of .  3 

Plowing,  Time  of .  3 

Principles  of  Semi-arid  Farming .  3 

Principles  of  Semi-arid  Farming,  Culture  of .  30 

Proso  .  16 

Questions  Sent  to  Other  Experiment  Stations  in  Semi-arid  Belt .  21 

Rainfall,  Average  Crop  Season .  26 

Rate  of  Seeding  .  11 

Root  Crops  . * .  17 

Bye  .  16 

Seed  Selection  . *. .  7 

Spring  Wheat  .  13 

Sub-Surface  Packer  .  5 

Summer  Culture  . - .  6 

Western  Wheat  Grass  .  18 

Winter  Wheat  .  14 


Bulletin  104. 


November,  1905 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College. 


A  Rust=Resisting  Cantaloupe 


BY  PHILO  K.  BLINN 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
Fort  Collins,  Colorado, 

1905. 


THE  AGRICULTURAL  EXPERIMENT  STATION. 

FORT  COLLINS,  COLORADO. 


THE  STATE  BOARD  OF  AGRICULTURE. 

TERM 


Hon.  P.  F.  SHARP,  President ,  •  • 

Hon.  HARLAN  THOMAS,  .... 

Hon.  JAMES  L.  CHATFIELD, 

Hon.  B  U.  DYE, . 

Hon.  B.  F.  ROCKAFELLOW 
Hon.  EUGENE  H.  GRUBB, 

Hon.  A.  A.  EDWARDS, . 

Hon.  R.  W.  CORWIN,  -  - 

Governor  JESSE  F.  McDONALD,  \  ~  . 

President  BARTON  O.  AYLESWORTH,  \  ex-°IJlcl0 


Denver 

EXPIRES 

-  1907 

Denver,  - 

-  1907 

Gypsum,  - 

-  1909 

Rockyford, 

1909 

Canon  City,  - 

1911 

Carbondale, 

-  1911 

Fort  Collins, 

1913 

Pueblo 

1913 

Executive  Committee  in  Charge. 

P.  F.  SHARP,  Chairman.  B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS 


Station  Staff. 

L.  G.  CARPENTER,  M.  S.,  Director  ....  Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S., . Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D., . -  Chemist 

W.  PADDOCK,  M.  S.,  -  - . Horticulturist 

W.  L.  CARLYLE,  M.  S., . Agriculturist 

G.  H.  GLOVER,  B.  S.,  D.  V.  M.t . Veterinarian 

W.  H.  OLIN,  M.  S.,  --------  Agronomist 

R.  E.  TRIMBLE,  B.  S.,  -  -  -  Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S.,  ------  -  Assistant  Chemist 

EARL  DOUGLASS,  M.  S., . Assistant  Chemist 

A.  H.  DANIELSON,  B.  S.,  -  -  -  -  Assistant  Agriculturist 

S.  ARTHUR  JOHNSON,  M.  S.,  -  -  -  -  Assistant  Entomologist 

B.  O.  LONGYEAR,  M.  S.,  -  -  -  -  Assistant  Horticulturist 

J.  A.  McLEAN,  A.  B.,  B,  S.  A.,  -  -  -  -  Animal  Husbandman 

P.  K.  BLINN,  B.  S.,  -  -  Field  Agent,  Arkansas  Valley,  Rockyford 


OFFICERS. 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S., . Director 

A.  M.  HAWLEY, . Secretary 

MARGARET  MURRAY,  ....  Stenographer  and  Clerk 


A  Rust  Resisting  Cantaloupe. 

# 

PHILO  K.  BLINN. 

The  cantaloupe  rust,  or  “blight”  as  it  is  called,  has  for  a  num¬ 
ber  of  years  inflicted  serious  injury  to  the  cantaloupe  industry  in 
Colorado  in  the  vicinity  of  Rocky  Ford,  and  recently  it  is  reported 
as  being  the  cause  of  similar  trouble  in  other  cantaloupe  growing 
sections  of  the  United  States. 

The  prevalence  of  the  disease  is  largely  affected  by  climatic 
conditions,  yet  in  localities  like  Rocky  Ford,  where  cantaloupes  are 
continually  grown,  the  soil  becomes  so  infested  with  the  spores  that 
its  development  is  as  regular  as  the  seasons,  yet  varying  somewhat 
as  to  the  loss  it  causes.  In  very  dry  seasons  its  development  may 
not  excite  much  notice,  other  than  the  dying  down  of  some  of  the 
leaves  in  the  centre  of  the  hill,  and  perhaps  a  few  yellow  spots  or 
specks  on  the  leaves  over  the  plant.  On  the  other  hand  if  the  sea¬ 
son  is  subject  to  rains  and  dews  its  development  is  very  disastrous 
to  the  crop.  Often  before  the  plants  reach  maturity  the  disease  so 
destroys  the  functions  of  the  leaves  that  the  cantaloupes  prema¬ 
turely  ripen,  and  have  no  desirable  qualities  for  table  use  and  are  a 
disappointment  to  everyone  handling  them.  A  few  days  of  cloudy, 
wet  weather  will  so  precipitate  the  disease  that  the  leaves  and  vines 
will  go  down  as  if  swept  by  a  blast  from  a  furnace;  the  cantaloupes 
will  become  soft  and  wilted  and  if  marketed  will  result  in  loss, 
though  it  sometimes  happens  that  if  rust  strikes  a  field  of  canta¬ 
loupes  at  about  the  time  the  melons  reach  maturity  it  will  so  hasten 
the  ripening  that  enormous  yields  are  sometimes  marketed  in  a  very 
few  days,  when  the  prices  are  high,  thus  resulting  in  advantage  to 
the  grower.  But  invariably  the  same  conditions  which  hasten  the 
ripening  of  one  field  will  also  hasten  others,  and  the  shipments  will 
increase  beyond  all  proportion  to  the  market  demands,  and  at  the 
same  time  the  quality  will  decrease  with  equal  rapidity  and,  before 
it  is  realized,  the  market  is  full  of  cantaloupes  inferior  in  quality, 
and  very  disheartening  returns  are  made. 

The  recurrence  of  these  rust  injuries  seems  to  be  more  com¬ 
mon  with  each  succeeding  season,  and  even  the  grower  who  by  care¬ 
ful  cultural  methods  or  favored  location  escapes  a  serious  attack,  is 
still  unable  to  get  satisfactory  returns, owing  to  the  demoralized  condi¬ 
tion  of  the  market  due  to  melons  from  rusted  areas.  It  seems  evi- 


Plate  V.  Two  plants  that  grew  in  the  same  hill,  one  killed  with 

rust,  the  other  rust  resisting. 


A  RUST  RESISTING  CANTALOUPE.  5 

dent  that  some  effective  remedy  or  means  of  control  must  be  found 
to  restore  confidence  in  the  melon  crop. 

The  Cause  of  the  Disease. — The  cantaloupe  rust  or  “Blight” 
so  called,  is  the  effect  of  a  parasitic  fungus  which  grows  and  devel¬ 
ops  on  the  tissues  of  the  plant.  It  has  been  named  “Macros- 
porimn  Cucumerinum,”  by  Ellis  and  Everhart.  It  spreads  and  de¬ 
velops  by  means  of  spores  that  are  carried  by  wind  and  other 
means  and  which  develop  when  conditions  are  favorable.  The 
idea  that  rain  and  dew  cause  the  rust  is  true  in  the  same  sense  that 
rain  causes  weeds, -it  simply  affords  conditions  favorable  for  devel¬ 
opment. 

Investigations  jor  Controlling  the  Disease. — In  1898,  H.  H. 
Griffin,  of  the  Colorado  Experiment  Station,  began  investigations  to 
control  the  disease.  He  carefully  conducted  field  tests  with  sprays 
of  different  fungicides,  and  Bordeaux  mixture  gave  promise  of  en¬ 
couraging  results,  but  owing  to  the  rapid  growing  nature  of  the 
cantaloupe  vines,  and  the  frequency  of  spraying  required,  with  its 
attendant  expense,  this  plan  proved  impracticable. 

By  a  series  of  tests,  it  became  evident  that  the  disease  is  not 
communicated  by  the  seed,  except  as  it  might  occasionally  occur 
from  spores  accidentally  lodging  with  the  seed. 

The  next  step  was  the  development  of  a  resistant  strain  of  can¬ 
taloupes. 

A  Rust-resisting  Cantaloupe. — In  the  summer  of  1903  a  close 
study  of  the  cantaloupe  fields  was  made  to  ascertain  if  any  varia¬ 
tion  existed  in  the  rust  resisting  tendency  of  the  various  strains  of 
Rocky  Ford  cantaloupe.  Owing  to  the  different  soil  conditions 
and  cultural  methods  on  different  farms,  and  the  varying  ages  of 
the  vines,  conclusions  were  difficult  to  draw,  as  all  the  vines  seemed 
to  be  affected  with  rust  to  some  extent,  and  eventually  all  suc¬ 
cumbed  to  its  attacks,  though  several  growers  claimed  to  have  can¬ 
taloupes  that  did  not  rust  “like  their  neighbors.” 

In  order  to  make  a  relative  comparison  of  the  point  in  ques¬ 
tion  a  small  quantity  of  seed  of  five  of  the  oldest  and  most  distinct 
strains  of  seed,  was  secured  from  those  who  were  propagating  them. 
This  seed  was  planted  on  a  plat  of  ground  that  in  1903  had  grown 
a  very  badly  rusted  crop  of  cantaloupes ;  two  rows  of  each  kind  were 
planted  May  9th,  1904,  with  a  row  of  watermelons  separating  each 
variety  to  prevent  their  vines  from  intermingling.  The  whole  plat 
had  uniform  conditions  of  culture  in  every  particular  and  the  vines 
of  each  variety  made  a  very  similar  growth.  About  Aug.  1st  the 
rust  began  to  develop  in  the  center  of  the  hills,  and  it  soon  became 
evident  that  the  disease  was  not  making  the  same  progress  on  all 
plants.  Some  of  the  hills  in  the  rows  planted  with  seed  fur¬ 
nished  by  Mr.  J.  P.  Pollock  remained  green  throughout  the  season, 


6 


bulletin  104. 


Plate  I.  Cantaloupe  hill  dead  with  rust. 


Plate  II.  Cantaloupe  hill  resisting  rust.  Both  views  taken  Sept.  24,  1904,  on 

adjacent  hills — J.  H.  Whittenburg  farm. 


A  RUST  resisting  cantaloupe. 


7 


and  also  produced  the  first  ripe  cantaloupe  from  the  plat,  Aug.  9th. 
A  few  days  later  the  other  strains  gave  a  greater  yield  of  early  mel¬ 
ons,  doubtless  due  to  the  rust,  which  soon  after  destroyed  ]  all  the 
plat  except  the  hills  mentioned. 

These  observations  were  verified  in  other  fields  planted  with 
the  Pollock  strain.  That  of  W.  B.  Ebberts,  east  of  Rocky  Ford, 
was  an  exceptionally  fine  field  of  cantaloupes,  and  revealed  green 
hills  here  and  there  over  the  patch  after  all  neighboring  fields  had 
been  destroyed  by  rust.  A  portion  of  the  cantaloupe  field  on  Mr. 
J.  H.  Whittenburg’s  place,  west  of  Rocky  Ford,  was  planted  with 
the  Pollock  seed  and  the  balance  with  what  is  known  as  the  “Blinn” 
strain.  By  Sept.  24th  the  portion  of  the  field  planted  with  the 
•  Pollock  seed  had  many  hills  that  remained  green,  when  the  balance 
of  the  field  was  brown  And  dead  with  rust. 

Plates  I  and  II  fairly  represent  the  contrast  in  the  two  portions 
of  the  field.  These  give  views  of  adjacent  hills.  Plate  II  is  a 
resistant  plant,  grown  from  the  Pollock  seed;  Plate  I  a  rusted 
hill  from  the  other  strain.  There  was  also  a  remarkable  contrast 
in  the  superior  quality  of  the  cantaloupes  produced  from  the  re¬ 
sistant  hills;  these  were  uniformly  sweet  and  spicy  and  possessed 
excellent  keeping  qualities. 

A  quantity  of  seed  from  the  rust  resisting  hills  was  selected  to 
carry  on  the  work  of  developing  a  rust  resisting  strain  of  canta¬ 
loupes. 

During  the  past  season,  1905,  this  resistant  seed  was  planted 
on  the  same  plat  of  ground  upon  which  the  experiments  had  been 
previously  conducted,  and  which  had  grown  in  succession  two  very 
badly  rusted  melon  crops,  the  idea  being  to  develop  the  resistant 
strain  in  as  adverse  rust  infested  conditions  as  possible,  to  thus  re¬ 
veal  the  most  strongly  resistant  plants. 

The  results  of  the  past  season  were  affected  somewhat  by  the 
destructive  hail  of  May  26th,  yet  fortunately  by  replanting,  and 
with  some  hills  which  survived  the  hail,  very  encouraging  results 
were  obtained.  Many  who  visited  the  plat  were  surprised  at  the 
great  contrast  between  the  rust  resisting  hills  and  those  from  ordi¬ 
nary  seed. 

Plates  III  and  IV,  views  taken  Sept.  20th,  reveal  the  contrast  not 
only  in  the  vines,  but  also  in  the  character  of  the  melons  produced 
on  the  respective  hills.  On  the  rust  resisting  hills  the  melons  were 
hidden  under  a  healthy  growth  of  vines  and  were  large,  solidly  net¬ 
ted,  with  thick,  firm  flesh,  small  seed  cavity  completely  filled  with 
seed.  On  the  rusted  hill  the  plants  were  almost  devoid  of  leaves 
and  the  small  melons  were  prematurely  ripe,  with  thin,  watery  flesh, 
large,  open  seed  cavity,  and  practically  of  no  market  value. 


8 


bulletin  104. 


Plate  V  shows  the  contrast  between  two  plants  which  grew  in 
the  .same  hill;  one,  entirely  dead  from  rust,  the  other  absolutely 
free  from  the  disease — this  view  taken  Oct.  1st.  This  hill  was 
grown  from  a  general  selection  of  Pollock  seed  and  reveals  the  ne¬ 
cessity  of  individual  plant  selection  to  eliminate  the  reverting  ten¬ 
dency  of  some  plants. 

Hills  grown  from  the  seed  of  one  resistant  cantaloupe  produced 
nearly  all  resistant  plants, — the  whole  row  showing  green  except 
an  occasional  vine  attacked  by  rust. 


Plate  III.  Rusted  hill,  showing  poor,  undeveloped  melons,  taken  Sept.  20,  1905 


Field  observations  were  again  made  to  verify  the  existence  of 
resistant  plants  in  fields  planted  with  Pollock  seed,  and  in  every 
instance  the  green  resistant  plants  could  be  seen  remaining  over 
the  field  after  the  balance  of  the  vines  were  dead  with  rust. 

During  the  shipping  season,  before  the  vines  had  gone  down 
with  rust  to  any  extent,  several  conspicuously  resistant  plants  in  the 
fields  of  Messrs.  C.  J.  Cover,  J.  B.  Ryan  and  I.  D.  Hale,  were  ob¬ 
served  and  marked  for  seed. 

Bach  grower  has  reported  that  these  hills  remained  green  till 
frost. 


A  RUST  RESISTING  CANTALOUPE. 


9 


The  relative  merits  of  the  Pollock  melon,  and  the  interest 
created  by  the  investigation  of  its  rnst  resisting  tendencies  led  many 
growers  to  plant  it  this  past  season,  and  many  other  growers  are 
anxious  for  any  evidence  toward  the  improvement  of  the  cantaloupe 
industry. 

The  fact  that  during  the  past  two  seasons,  several  names  have 
been  given  to  the  Pollock  cantaloupe,  such  as  “Eden  Gem,’’  “Net¬ 
ted  Rocks,”  and  other  suggestive  titles,  also  that  several  Associ- 


Plate  IV.  Rust  Resistant  Hill,  showing  fine  qualities  of  netting  and  thick 

flesh,  taken  Sept.  20,  1905. 


stions  and  commission  men  are  insisting  that  their  growers  shall 
plant  only  this  strain,  seems  to  be  good  evidence  of  its  practical 
merits. 

In  the  light  of  investigation,  the  rust  resisting  tendencies  of 
the  Pollock  strain,  seem  to  offer  the  most  immediate  solution  of 
the  rust  problem.  With  this  object  in  view,  we  hope  to  induce  the 
cantaloupe  growers  to  consider  rust  and  disease  resisting  plants  as 


IO 


bulletin  104. 


an  important  feature  in  seed  selection  and  lead  them  to  furnish  in¬ 
formation  that  will  assist  in  securing  that  end. 

As  a  matter  of  information  regarding  this  strain  of  cantaloupes, 
an  inquiry  was  directed  to  Mr.  J.  P.  Pollock  asking  for  a  short  his¬ 
tory  of  the  cantaloupe  while  it  was  in  his  hands.  The  following 
is  his  reply: — 


1908  Colorado  Avenue,  Colorado  Springs,  Oct.  6th,  1905. 
Mr.  P.  K.  Blinn, 

Dear  Sir: — 

Yours  at  hand;  I  note  what  you  say  regarding  the  Pollock  cantaloupe 
with  pleasure,  mainly  because  if  you  are  correct  in  your  conclusions  as 
to  its  rust  resisting  qualities,  I  have  been  instrumental  in  doing  good  to 
the  community. 

Now  as  to  its  history;  I  began  growing  the  strain  nine  years  ago  in 
Holbrook,  my  first  experience  in  melon  culture  and  farming  in  Colorado. 

I  got  two  lots  of  seed  from  Ellingwood  and  Houck,  one  at  50  cts.  per 
lb.  and  the  other  at  $3.00  per  lb. ;  the  50c  seed  grew  large  melons,  too  large, 
not  one  tenth  being  of  a  size  to  crate.  The  $3.00  seed  produced  good  can¬ 
taloupes,  most  of  them  good  sized  and  very  heavy  netted,  not  a  short 
melon  but  correct  in  length ;  I  saved  my  seed  selecting  the  proper  size 
and  netting, — you  may  draw  your  own  conclusions  as  to  whether  there 
was  cross  fertilization  producing  the  origin  of  my  future  strain. 

The  next  year  I  planted  at  Bocky  Ford;  I  had  a  fine  growth  of  vines 
and  setting  of  cantaloupes,  I  distinctly  remember  the  heavy  growth  of 
vines.  It  was  my  first  experience  with  plenty  of  water,  and  I  over¬ 
watered  and  the  rust  struck  the  patch,  and  I  had  quite  a  failure;  the  whole 
patch  was  ruined  and  I  was  soon  counted  out  at  the  platform  on  the  score 
of  rusted  vines.  However,  I  selected  my  seed  from  the  patch,  selecting  a 
large  sized  melon  with  a  white  close  netting,  and  a  perfect  cantaloupe  as 
I  remember  it,  in  the  midst  of  the  rusted  vines;  I  never  had  much  trouble 
with  rust  after  that,  and  in  the  light  of  your  conclusions  as  to  its  rust  re¬ 
sisting  tendencies,  I  now  believe,  I  unwittingly  selected  a  rust  resisting 
melon,  as  the  rest  of  my  crop  were  slick  melons  that  failed  to  mature. 
Thereafter  I  always  had  my  eye  on  that  same  type  of  melon  in  selecting 
my  seed;  it  was  a  full  large  sized  melon,  with  netting  over  the  blossom 
end;  not  a  long  melon,  but  rather  inclined  to  be  short,  but  it  had  the  quali¬ 
ties.  By  selection  I  reduced  the  size  of  my  cantaloupes  down  till  the  last 
two  years  that  I  grew  them  they  averaged  well  to  crate  nicely.  I  often 
thought  of  changing  my  stock  of  seed, but  after  going  through  the  season, 
having  very  little  trouble  with  culls  or  inferior  melons  and  the  quality 
seeming  to  me  superior  in  comparison  with  anything  I  could  get  hold  of, 
I  stayed  with  it.  I  could  easily  see  that  they  had  peculiarities  of  their 
own  compared  with  other  cantaloupes. 

Now  if  the  using  of  my  name  in  this  connection  meets  with  your  ap¬ 
proval,  it  is  certainly  satisfactory  to  me,  and  I  will  feel  honored. 
Wishing  you  success  in  the  work  and  asking  for  a  copy  of  your  Bulletin, 
I  am, 

Yours  truly. 

J.  P.  Pollock. 

This  bit  of  history  reveals  why  this  strain  of  seed  shows  re¬ 
sistant  tendency;  it  has  a  line  of  selection  to  that  end,  though  un¬ 
intentional  at  the  time.  There  is  an  old  law  in  nature  called  the 
“Survival  of  the  fittest,”  it  applies  to  plants  as  well  as  animals;  it 
simply  means  that  in  nature  individuals  that  are  able  to  grow  and 
develop  in  the  midst  of  adverse  conditions  are  thus  naturally  se¬ 
lected  to  resist  the  attacks  of  their  enemies.  It  is  for  this  reason 


A  RUST  RESISTING  CANTALOUPE. 


I  I 

that  our  native  plants  and  weeds  are  so  little  affected  by  adverse 
conditions,  while  our  cultivated  crops  are  so  susceptible.  For 
many  generations  under  cultivation,  they  have  been  developed  for 
certain  purposes,  and  the  vital  line  of  selection  has  been  neglected. 
This  is  especially  true  in  regard  to  some  cultivated  flowering 
plants;  their  existence  depends  entirely  upon  the  care  and  protec¬ 
tion  of  man.  If  they  were  left  to  their  natural  enemies,  they 
would  soon  become  extinct. 

No  work  in  connection  with  agriculture  is  so  important  in  its 
results  as  that  of  seed  selection.  Too  long  it  has  been  merely  seed 


Plate  VI.  Single  plant  that  produced  sixteen  large  cantaloupes. 


saving ,  and  if  selection  has  been  considered  it  has  been  along  nar¬ 
row  lines,  perhaps  size,  form  or  appearance  has  been  considered 
at  the  expense  of  quality,  or  possibly  it  has  been  the  quality  at  the 
expense  of  vitality. 

A  standard  of  perfection  covering  all  the  essential  points  in 
the  development  of  a  perfect  cantaloupe  would  assist  the  grower 
in  keeping  his  selection  so  balanced  as  to  strengthen  or  build  up 
any  weakness,  his  strain  of  seed  might  reveal.  To  this  end  the 
following  points  might  be  considered  as  a  schedule  for  selection. 


12 


bulletin  104. 


Schedule  for  Seed  Selection. 

P-rolific  yielding, 

E-arly  maturing, 

R-esisting  tendency, 

F-orm,  size  and  netting, — ideal, 

E-picurean  qualities,  sweet  and  spicy, 
C-avity,  small,  well  filled, 

T-exture,  smooth  and  firm. 

While  the  field  is  growing,  select  and  mark  any  individual 
plants  that  show  exceptional  merit  along  the  lines  of  prolific  yield, 
early  maturity  or  resistant  power.  That  such  variation  frequently 
occurs  is  plainly  shown  by  the  field  observations  of  the  past  three 
years;  many  plants  were  observed  which  produced  only  three  or 
four  cantaloupes  during  the  entire  season,  while  in  one  instance, 
shown  in  Plate  VI,  sixteen  large  cantaloupes  were  produced  from  one 
plant,  which  would  be  a  very  large  yield  for  three  or  four  ordinary 
plants.  The  variation  in  maturing  was  revealed  in  the  compara¬ 
tive  test  of  the  five  strains  of  seed  before  mentioned.  Ten  days 
elapsed  between  the  first  ripe  melon  on  one  strain,  and  the  first  of 
another,  although  the  rows  were  given  uniform  conditions. 

The  variation  in  resistant  power  has  already  been  indicated. 

One  very  important  feature  of  the  work  of  seed  selection  is  the 
marking  of  individual  plants  which  show  desirable  qualities.  The 
seed  should  be  saved  separately,  labeled  and  grown  by  itself,  thus 
fixing  in  the  strain  these  desirable  traits. 

In  the  past  the  seed  saving  has  been  too  much  from  a  general 
selection  of  the  melons  without  regard  to  the  merits  of  the  vines 
from  which  they  grew;  and  also  a  common  error  has  been#in  giving 
too  much  attention  to  the  external  points  of  the  melon  without 
considering  its  internal  qualities.  This  is  well  illustrated  in 
Plates  VII  and  VIII  which  show  a  choice  pile  of  cantaloupes  selected 
for  outside  appearance  only ;  the  other  view  shows  some  of  the  same 
melons  cut  in  half  revealing  the  undesirable  large  open  cavity  and 
thin  flesh  of  some,  and  the  solid,  well  filled  cavity  and  thick  flesh  of 
others. 

When  the  marked  hills  reach  maturity  the  vines  which  reveal  the 
most  uniform  sized  cantaloupes  of  ideal  form  and  netting  should 
be  taken  as  the  basis  for  selection.  That  the  size  as  well  as  other 
qualities  is  affected  by  seed  selection  is  brought  out  in  the  letter 
of  Mr.  J.  P.  Pollock,  in  which  he  states  that  he  “reduced  the 
size  down  until  they  averaged  well  to  crate.” 

There  are  many  conditions  which  may  affect  size  and  to  some 
extent  each  grower  should  study  his  soil  from  the  standpoint  of  the 
melons  which  it  produces,  and  govern  his  selection  accordingly. 

The  netting  of  a  cantaloupe  has  long  been  considered  an  at¬ 
tractive  fancy  feature  and  without  question  it  is  the  essence  of  its 


A  RUST  RESISTING  CANTALOUPE 


13 


Plate  VII.  Pile  of  cantaloupes  selected  from  outward  appearance  only. 


Plate  VIII. 


Some  of  the  same 


cantaloupes 

qualities. 


showing  contrast  of  internal 


14 


buu^tin  104. 


appearance  on  the  market,  and  experience  reveals  that  it  has  a 
value  in  protecting  the  keeping  qualities  of  the  melons  on  long 
shipments. 

The  words  “Rocky  Ford”  scratched  on  the  surface  of  a  green 
melon  appeared  in  the  netting  at  maturity,  thus  showing  that  the 
netting  of  a  cantaloupe  is  merely  a  tracery  of  callous  formed  by 
the  natural  cracking  of  the  surface  of  the  melon. 

By  observation  and  tests  it  is  shown  that  a  close  netted  melon 
does  not  lose  weight  by  evaporation  as  rapidly  as  one  less  covered 
with  netting,  thus  its  keeping  and  shipping  qualities  are  largely 
determined  by  the  amount  of  netting  on  its  surface. 

Plate  IX  represents  a  former  ideal  Rocky  Ford  Netted  Gem,  a 
melon  characterized  by  a  close  heavy  netting  divided  by  clear  cut 
sectors.  But  the  tendency  of  these  stripes  is  to  widen  under  care¬ 
less  selection,  and  in  view  of  the  superior  keeping  qualities  of  the 
“solid  net,”  the  old  ideal  is  giving  way  to  a  type  represented  in 
Plate  X  which  is  a  result  of  a  cross  of  the  Pollock  strain  and  the 
melon  shown  in  Plate  IX,  known  as  the  “Blinn”  strain.  The  form 
is  more  nearly  perfect  to  fit  the  standard  crates  than  the  ronnd  type 
characterizing  the  Pollock  strain,  and  its  internal  qualities  are  in 
keeping  with  the  external  appearance. 

The  eating  qualities  of  a  cantaloupe  are  the  ultimate  test  of 
its  perfection.  A  cantaloupe  produced  from  a  strong  healthy  vine 
and  yet  not  having  a  sweet  spicy  flavor,  should  never  be  saved  for 
seed. 

The  small  cavity,  solidly  filled  with  seed,  ^  thick  flesh  with 
smooth,  firm  texture,  are  obvious  points  in  the  value  of  a  marketable 
cantaloupe.  These  with  many  minor  points  should  be  zealously 
guarded  by  the  careful  seed  selector. 

There  is  no  absolute,  fixed  relation  existing  between  the  points 
of  the  above  schedule.  Thus,  the  selection  of  melons  for  resistant 
powei  only,  will  not  insure  netting  or  other  qualities.  On  the 
other  hand,  an  ideally  perfect  melon,  if  unable  to  resist  rust,  would 
be  a  failure;  but  careful  attention  to  all  these  details  in  dne  pro¬ 
portion,  will  result  in  a  melon  like  that  shown  in  Plate  X, — a  can¬ 
taloupe  having  a  “money  basis.” 


A  rust  resisting  cantaloupe. 


- 


Plate  IX.  An  old  ideal  of  perfection.  From  Bulletin  85,  1903. 


Plate  X.  A  perfect  Pollock  cantaloupe,  selected  for  resistant  tendency 

cantaloupe  with  a  money  basis.” 


. 


-  . . 


■ 


Bulletin  105. 


November,  1905. 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College. 


A  New  Apple  Rot. 


BY  B.  O.  LONGYEAR. 


1 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
FORT  COLLINS,  COLORADO 

1  905 


The  Agricultural  Experiment  Station, 

FORT  COLLINS,  COLORADO. 


THE  STATE  BOARD  OF  AGRICULTURE. 

Term 

Expires 

Hon.  P.  F.  SHARP,  President ,  -  -----  Denver.  1907 

Hon.  HARLAN  THOMAS,  - . Denver.  1907 

Hon.  JAMES  L.  CHATFIELD, . Gypsum.  1909 

Hon.  B.  U.  DYE, . -  Rockyford.  1909 

Hon.  B.  F.  ROCKAFELLOW, . Canon  City.  1911 

Hon.  EUGENE  H.  GRUBB,  -----  Carbondale.  1911 

Hon.  A.  A.  EDWARDS,  ------  Fort  Collins.  1913 

Hon.  R.  W.  CORWIN,  --------  Pueblo.  1913 

Governor  JESSE  F.  McDONALD,  [  m  . 

President  BARTON  O.  AYLESWORTH,  j  ex-ojjicw. 


Executive  committee  in  charge. 

P.  F.  SHARP,  Chairman. 

B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS. 


STATION  STAFF. 

L.  G.  CARPENTER,  M.  S.,  Director,  -  -  -  Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S., . Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D.,  - . Chemist 

WENDELL  PADDOCK,  M.  S.,  -  -  -  -  -  -  Horticulturist 

W.  L.  CARLYLE,  M.  S., . Agriculturist 

G.  H.  GLOVER,  B.  S.,  D.  V.  M.,  ------  Veterinarian 

Wr.  H.  OLIN,  M.  S.,  -  -  -  -  -  -  -  -  -  Agronomist 

R.  E.  TRIMBLE,  B.  S.,  -  -  -  -  Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S.,  -  -  -  -  -  -  -  Assistant  Chemist 

EARL  DOUGLASS,  M.  S., . Assistant  Chemist 

A.  H.  DANIELSON,  B.  S.,  -  -  -  -  Assistant  Agriculturist 

S.  ARTHUR  JOHNSON,  M.  S  ,  -  -  -  -  Assistant  Entomologist 

B.  O.  LONGYEAR,  B.  S., . Assistant  Horticulturist 

J.  A.  McLEAN,  A.  B.,  B.  S.  A.,  -----  Animal  Husbandman 

E.  B.  HOUSE, . Assistant  Irrigation  Engineer 

P.  K.  BLINN,  B.  S.,  -  -  Field  Agent,  Arkansas  Valley,  Rockyford 


Officers. 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S.,  -  -  -  -  -  -  -  Director 

A.  M.  HAWLEY, . Secretary 

MARGARET  MURRAY, . Stenographer  and  Clerk 


PLATE  I.— Four  Ben  Davis  apples  showing  the  Alternaria  Rot  in  the  blossom  end  (on  the  right). 
Three  apples  artificially  inoculated  with  spores  of  the  Alternaria  (on  the  left). 


An  Apple  Rot  Due  to  An 
Undescribed  Species  of  Alternaria. 


BY  B.  O.  LONGYEAR. 

history  and  distribution. 

Among*  the  comparatively  few  diseases  of  orchard  fruits,  which 
occur  in  the  state  of  Colorado,  probably  the  most  widely  distributed 
and  common  one  is  a  decay  of  apples  and  pears  due  to  an  appar¬ 
ently  undescribed  species  of  Alternaria.  This  decay  was  first  met 
with  by  the  writer  at  the  Michigan  Agricultural  Experiment  Station 
in  the  winter  of  1904.  While  investigating  the  decays  of  stored 
apples  at  that  place,  a  single  specimen  was  found  showing  a  decay 
of  unfamiliar  appearance.  A  tube  culture  was  made  from  spores 
obtained  by  placing  this  specimen  in  a  moist  chamber  for  several 
days,  and  inoculations  of  sound  fruit  were  made  which  demon¬ 
strated  the  ability  of  the  fungus  to  induce  the  decay. 

At  this  Station  the  fungus  was  first  reported  in  November, 
1902,  and  specimens  were  secured  for  study  by  Professor  W.  Pad- 
dock,  who  recognized  the  fungus  as  being  a  species  of  Alternaria. 
Pie  also  conducted  some  inoculation  experiments  with  the  fungus 
and  made  the  first  report  of  it  in  the  Experiment  Station  report  of 
1904.  Investigation  shows  it  to  be  of  quite  common  occurrence  in 
this  State  and  it  has  been  also  found  in  the  core  cavity  of  one 
variety  of  apples  grown  in  California. 

Thus,  while  this  decay  evidently  occurs  over  a  wide  range,  the 
fact  that  it  has  thus  far  been  unnoticed,  indicates  that  it  is  probably 
not  destructive  to  any  extent  in  other  regions. 

CHARACTER  OR  THE  DISEASE  ON  THE  APPUE. 

In  the  case  of  the  apple,  so  far  as  studied,  the  fungus  is  con¬ 
fined  to  the  fruit,  its  most  common  point  of  attack  being  at  the 
blossom  end.  The  affected  fruits  usually  show  a  dark  purplish 
brown,  slightly  sunken  area  at  the  base  of  the  sepals.  This  area 
may  remain  small  and  scarcely  noticeable  for  a  long  time,  but  when 
the  fruit  is  placed  in  storage  it  is  apt  to  increase  in  extent  until  the 
fruit  is  entirely  decayed.  During  the  past  season  specimens  were 
found  in  which  the  blossom  end  of  the  apple  was  cracked  open  and 
a  considerable  area  of  the  discolored  tissue  surrounded  the  rupture, 
but  this  is  not  the  usual  manner  of  attack.  It  seems  probable  in 


Picked  from  the  trees  in  September. 


A  New  Appre  Rot. 


7 


these  cases  that  the  fungus  was  not  the  cause  of  the  cracking,  but 
merely  gained  a  foothold  in  the  wound.  Other  wounds  in  the  fruit, 
such  as  those  caused  by  the  larvae  of  the  codling  moth,  are  fre¬ 
quently  the  point  of  attack  of  this  fungus. 

The  rotting  due  to  this  fungus  is  usually  not  so  rapid  as  that 
caused  by  some  of  the  soft  rot  fungi.  Hence,  fruit  that  is  already 
affected  by  the  Alternaria  in  some  cases  succumbs  to  some  of  the 
more  rapidly  working  rots  which  not  infrequently  seem  to  follow 
it.  The  affected  tissue  is  not  greatly  softened  by  this  fungus,  but 
by  drying  out  finally  changes  to  a  shrivelled  dark  brown  mass  simi¬ 
lar  to  that  produced  by  the  mummifying  effects  of  the  brown  rot  of 
stone  fruits. 

In  many  cases,  however,  no  external  evidence  of  the  presence 
of  the  fungus  is  noticeable  until  the  apple  is  cut  through  when  the 
core  cavity  is  found  to  be  blackened  or  discolored.  In  the  majority 
of  such  cases  the  parchment-like  lining  of  the  seed  cavity  is  the  only 
part  showing  the  discoloration  which,  in  mild  cases,  appears  in  the 
form  of  brownish  or  blackish  streaks  or  stains.  The  seeds,  too,  are 
usually  coated  with  a  dark  colored  growth  of  the  mycelium.  In 
badly  affected  specimens,  however,  the  seed  cavity  is  nearly  filled  with 
fungous  threads,  while  the  discoloration  extends  into  the  surrounding 
flesh  of  the  fruit  to  a  greater  or  less  extent. 

This  invasion  of  the  core  by  the  fungus  appears  to  be  most 
common  in  certain  varieties  of  the  apple,  among  which  the  Wine 
Sap  is  especially  subject  to  this  form  of  attack.  And  in  the  worst 
cases  this  variety  shows  some  eyidence  of  the  presence  of  the 
blackened  core  by  a  slightly  contracted  appearance  and  yellowed 
color  of  the  blossom  end.  Fruit  which  is  of  good  size  and  normal 
depth  of  color  seems  usually  to  indicate  freedom  from  this  condition 
of  the  core,  while  fruit  of  small  size  with  unusually  light  or  dark 
color  is  frequently  found  to  be  affected. 

The  reason  why  certain  varieties  of  the  apple  are  particularly 
subject  to  the  blackened  seed  cavity  is  found  in  a  structural  peculiar¬ 
ity  of  such  varieties.  Thus  a  longitudinal  section  through  such  an 
apple  usually  shows  a  very  deep  calyx  tube,  which,  in  many  cases, 
extends  to  or  meets  the  core,  or  even  opens  into  it.  In  such  cases 
the  fungus  has  evidently  reached  the  core  through  this  passageway 
by  following  the  united  styles  and  the  inner  wall  of  the  calyx  tube. 
(See  Plate  I  and  III). 

ON  THE  PEAR. 

In  the  case  of  the  pear,  the  fungus  has  been  found  on  fruit, 
leaves,  and  young  sprouts  at  base  of  the  tree.  The  fruit  seems 
liable  to  attack  at  almost  any  point,  in  observed  cases  the  stems  being 
frequently  blackened  and  the  surface  spotted  irregularly.  In  the 


COLO.  AG.EXPT.  STA 


PLATE  III. — Vertical  section  through  a  Winesap  apple  showing  the  very  deep  calyx  tube 
meeting  the  seed  cavity,  which  is  darkened  by  the  fungus  (upper  figure). 

(a)  Young  apples,  fallen  from  the  tree,  showing  the  Alternaria  after  being  kept  in  moist 
chamber,  (b)  Young  apples  and  a  fruit  spur  blackened  with  the  fungus,  after  remaining 
on  the  tree  over  winter. 

Leaf  of  Keiffer  pear  affected  with  the  Alternaria  (lower  figure). 


A  New  Apple  Rot. 


9 


latter  case,  too,  the  skin  of  the  fruit  is  often  cracked  in  the  affected 
areas  apparently  from  loss  of  moisture. 

On  the  leaves  of  the  pear  the  fungus  produces  brown  spots  of 
considerable  size  which  are  often  situated  along  the  margin  or 
scattered  over  the  surface  in  an  irregular  manner.  (See  Plate  II 
and  III). 

MICROSCOPIC  characters. 

The  rotting  effects  of  this  fungus  are  due  to  the  invasion  of 
the  tissues  of  the  plant  by  numerous  branching  threads  or  hyphse 
of  mycelium.  Thus  a  microscopic  examination  of  the  decayed  part 
of  an  apple  or  pear  reveals  the  presence  of  this  mycelium  in  the  form 
of  an  intricate  network.  These  hyphse  vary  considerably  in  diame¬ 
ter  in  some  cases  being  so  slender  as  to  be  seen  with  difficulty  under 
even  a  high  power.  In  numerous  instances,  the  mycelium  may  be 
found  in  the  cell  cavity,  in  which  case  the  slender  hyphse  are  often 
coiled  to  some  extent.  Within  the  affected  tissues  the  mycelium  is 
nearly  hyaline,  or  but  slightly  yellowish  in  color  and  contains  num¬ 
erous  minute  oil  drops ;  but  as  the  fruiting  or  spore-bearing  portions 
of  the  mycelium  are  reached,  the  hyphse  assume  a  brownish  color. 
The  conidiophores,  or  spore-bearing  branches,  possess  rather  thick¬ 
er  walls  than  the  feeding  part  of  the  mycelium  and  are  freely  septate 
near  the  terminus. 

The  spores,  conidia,  are  characteristic  of  those  of  the  genus 
Alterncria.  When  seen  in  mass  they  appear  blackish  olive,  but  are 
of  a  brownish  color  when  seen  under  the  microscope.  They  differ 
much  in  size  and  shape,  as  well  as  in  the  number  of  cells  composing 
them,  varying  from  one  cell  in  the  smallest  to  ten  or  twelve  cells  in 
the  largest.  They  are  produced  in  simple  or  slightly  branched  chains 
with  a  narrowed  portion,  consisting  of  one  or  more  lengthened  cells, 
joining  the  spores.  Thus,  when  the  larger  spores  are  separated  they 
usually  possess  a  somewhat  flask-shaped  form,  the  larger  end  rep¬ 
resenting  the  base  or  point  nearest  the  conidiophore. 

Spores  may  often  be  found  by  examining  the  calyx  end  of 
affected  specimens  of  fruit,  but  are  obtained  most  readily  by  placing 
such  fruit  in  a  moist  chamber  for  a  few  days. 

The  spores  germinate  readily  in  water,  each  cell  being  capable 
of  sending  out  a  germ  tube,  and  even  portions  of  the  conidiophores 
frequently  act  in  the  same  manner.  While  the  spores  are  capable 
of  germinating  as  soon  as  mature,  if  conditions  of  moisture  and 
temperature  are  not  favorable  they  will  remain  dormant  during  the 
remainder  of  the  season  or  until  the  conditions  are  suitable  for 
growth.  (Plate  IV). 

TIME  AND  MANNER  OE  INEECTION. 

While  the  matter  of  infection  has  not  been  investi¬ 
gated  to  any  great  extent,  it  appears  from  observations  made,  in 


PLATE  IV. — Microscopic  characters  of  the  Alternaria;  (a)  mycelial  threads 
within  a  cell  from  rotting  pear;  (b)  hyphm  showing  the  variable  size  of  the 
mycelium;  (c)  mature  spores  from  a  culture;  (d,  e)  manner  of  spore-formation 
from  'culture;  (f)  two  spores  germinating  in” water,  at  the  end  of  three 
hours. 


A  New  Apple  Rot. 


11 


the  case  of  the  apple,  that  the  fungus  gains  a  foothold  on  the  with¬ 
ered  stamens  and  stigmas  which  remain  in  the  blossom  end  of  the 
fruit.  This  may  quite  often  occur  early  in  the  season  soon  after 
the  flowering  period  and  while  the  fruit  is  just  forming.  For, 
when  the  withered  stamens  and  stigmas  are  placed  in  a  moist  cham¬ 
ber,  at  this  time,  the  Alternaria  frequently  develops.  The 
rotting  effects  of  the  disease,  however,  do  not  usually  appear  until 
after  the  growing  period  is  nearly  past  and  when  the  ripening  stage 
is  reached.  Thus  it  would  appear  that  the  fungus  is  not  capable  of 
making  much  headway  while  the  tissues  are  in  a  young,  growing 
condition  and  when  the  vital  processes  are  most  active,  but  behaves 
more  in  the  nature  of  a  ripe  rot  fungus  and  is,  therefore,  not 
strictly  parasitic.  This  is  also  suggested  from  the  fact  that  young- 
growing  apples  when  inoculated  with  the  fungus  were  not  much 
affected  by  it. 

The  principal  source  of  infection  in  spring  appears  to  be  the 
diseased  fruits  of  last  year,  which  remain  in  the  orchard  in  a  shriv¬ 
elled  and  blackened  condition,  either  lying  on  the  ground,  or  some¬ 
times  left  clinging  to  the  fruit  spurs.  Young  fruit  which  has  failed 
to  develop  fully,  perhaps  due  to  imperfect  pollination,  is  frequently 
found  to  be  permeated  with  this  fungus,  after  having  withered 
upon  the  tree.  In  such  cases  the  fungous  threads  within  the  tissues 
of  these  mummified  fruits  are  capable  of  producing  a  crop  of  spores 
when  the  conditions  are  favorable  the  following  spring.  Some  of 
these  old  diseased  parts,  when  placed  in  a  moist  chamber,  gave  rise 
to  a  vigorous  growth  of  conidia-bearing  threads,  the  spores  of  which 
started  the  rot  when  used  in  making  inoculations.  The  fungus 
evidently  hibernates  also  on  the  twigs  and  fruit  spurs,  as  it  was  ob¬ 
tained  from  them  during  the  winter  season.  Wounds  in  the  fruit 
caused  by  the  larvae  of  the  codling  moth  frequently  give  entrance 
to  the  Alternaria.  (Plate  III). 

ARTIFICIAL  CULTURES  AND  INOCULATIONS. 

Numerous  cultures  of  the  fungus  have  been  made  in  the  labora¬ 
tory,  using  several  different  culture  media.  From  these,  inoculations 
of  sound,  ripe  fruit  were  performed  by  inserting  the  spores  of  the 
fungus  into  punctures  made  with  a  sterilized  needle.  Usually  in  two 
or  three  days  the  point  inoculated  begins  to  show  a  surrounding 
area  of  decaying  tissue,  which  widens  rather  slowly  but  steadily 
until  the  entire  fruit  is  involved.  The  only  fruit  besides  the  pear 
and  apple  that  has  been  inoculated  with  this  fungus  is  the  tomato, 
but  in  such  cases  it  made  almost  no  progress.  (Plate  I). 

varieties  affected  and  extent  of  injury. 

In  the  case  of  the  apple  the  varieties  reported  as  most  com¬ 
monly  subject  to  the  Alternaria  rot  are  the  Lawver,  Foy,  Mann, 


12 


Bulletin  105. 


Dominie,  Jonathan  and  Ben  Davis,  while  the  Winesap  appears  to 
be  most  commonly  affected  in  the  seed  cavity,  as  previously  men-  . 
tioned.  Some  of  these  varieties  are  among  those  which  are  re¬ 
ported  as  dropping  their  fruit  badly  in  some  seasons  during  June 
and  July,  but  whether  or  no  the  fungus  plays  any  part  in  this  matter 
has  not  been  determined. 

Among  pears,  the  Keiffer  is  the  only  variety  which  has  thus 
far  shown  any  liability  to  attack  from  this  fungus,  although  in  the 
cases  observed  other  varieties  were  growing  in  the  same  orchard. 

The  extent  of  the  injuries  due  to  this  Alternaria  have  not  been 
estimated  even  approximately.  It  is  apparently,  however,  not  a 
destructive  fungous  disease,  as  compared  with  some  which  attack 
the  apple  and  pear  in  more  humid  regions.  It  is  doubtless  capable 
of  doing  considerable  damage,  however,  to  the  fruit  of  susceptible 
varieties,  some  of  which  have  been  reported  as  almost  failing  to 
bring  their  fruit  to  maturity. 

CONTROLLING  THE  DISEASE. 

In  the  absence  of  any  experimental  work  in  the  control  of  the 
Alternaria  rot  the  methods  for  combating  the  fungus  are  necessarily 
suggestive.  Attempts  to  control  the  fungus  in  one  orchard,  by  the 
use  of  Bordeaux  mixture,  indicate  that  it  can  be  much  reduced. 
Whenever  this  fungus  becomes  troublesome  the  following  measure? 
are  suggested : 

(a)  Clean  culture,  thereby  covering  up  in  spring  all  diseased, 
fruit  that  is  left  on  the  ground  under  the  trees  besides  keeping  the  trees  in  a 
state  of  good  health. 

(b)  The  use  of  some  fungicide  as  a  spray,  the  first  application  being 
a  strong  copper  sulphate  solution,  one  pound  to  twenty-five  gallons  of  watei, 
applied  just  before  the  buds  open  in  spring.  The  standard  Bordeaux  mix¬ 
ture  should  be  used  after  blossoming,  making  one  or  more  applications  dur¬ 
ing  the  growing  season  as  may  appear  necessary.  This  may  be  used  in  con 
junction  with  the  poison  mixtures  applied  for  the  control  of  the  codlin, 
moth,  thus  saving  extra  labor  and  time. 

(c)  While  it  is  very  improbable  that  the  disease  will  ever  prov 
uncontrollable  by  the  preceding  means,  should  that  occur,  it  would  be  ad 
visable  to  discontinue  the  growing  of  varieties,  which  are  particularly  sus 
ceptible  'to  the  attacks  of  this  fungus. 


\  • 

> 


1. 

■ 


Bulletin  106.  December,  1905 

The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College. 


PRUNING  FRUIT  TREES 


BY  WENDELL  PADDOCK 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
Fort  Collins,  Colorado, 

1905. 


THE  AGRICULTURAL  EXPERIMENT  STATION, 


FORT  COLLINS,  COLORADO. 


THE  STATE  BOARD  OF  AGRICULTURE. 

TERM 

EXPIRES 

Hon.  P.  F.  SHARP,  President , . Denver  -  1907 

Hon.  HARLAN  THOMAS,  ....  Denver,  -  -  1907 

Hon.  JAMES  L.  CHATFIELD,  -  -  Gypsum,  -  -  1909 

Hon.  B.  U.  DYE, . Rocky  ford,  -  1909 

Hon.  B.  F.  ROCKAFELLOW  -  Canon  City,  -  1911 

Hon.  EUGENE  H.  GRUBB,  ....  Carbondale,  -  1911 

Hon.  A.  A.  EDWARDS, . Fort  Collins,  1913 

Hon.  R.  W.  CORWIN,  -  ....  Pueblo  -  1913 

Governor  JESSE  F.  McDONALD,  \  ^  . 

President  BARTON  O.  AYLESWORTH,  T  ^ 


A.  M.  HAWLEY,  Secretary  EDGAR  AVERY,  Treasurer 


Executive  committee  in  Charge. 

P.  F.  SHARP,  Chairman.  B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS 


STATION  STAFF. 


L.  G.  CARPENTER,  M.  S.,  Director 
C.  P.  GILLETTE,  M.  S.,  - 

W.  P.  HEADDEN,  A.  M.,  Ph.  D.,  - 

W.  PADDOCK,  M.  S., 

W.  L.  CARLYLE,  M.  S., 

G.  H.  GLOVER,  B.  S.,  D.  V.  M., 

W.  H.  OLIN.  M.  S., 

R.  E.  TRIMBLE,  B.  S.(  -  -  - 

F.  C.  ALFORD,  M.  S., 

EARL  DOUGLASS,  M.  S.,  - 

A.  H.  DANIELSON,  B.  S.,  - 

S.  ARTHUR  JOHNSON,  M.  S.,  - 

B.  O.  LONGYEAR,  B.  S., 


-  Irrigation  Engineer 
Entomologist 
Chemist 
Horticulturist 
Agriculturist 
-  Veterinarian 
Agronomist 
Assistant  Meteorologist 
Assistant  Chemist 
Assistant  Chemist 
Assistant  Agriculturist 
Assistant  Entomologist 
Assistant  Horticulturist 


J.  A.  McLEAN,  A.  B.,  B.  S.  A.,  -  -  -  -  Animal  Husbandman 

E.  B.  HOUSE  -----  Assistant  Irrigation  Engineer 

O.  B.  WHIPPLE,  B.  A.,  -  -  -  Assistant  Horticulturalist 

P.  K.  BLINN,  B.  S.,  -  -  Field  Agent,  Arkansas  Valley,  Rockyford 


OFFICERS. 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S., . Director 

A.  M.  HAWLEY, . -  -  -  Secretary 

MARGARET  MURRAY,  ....  Stenographer  and  Clerk 


Pruning  fruit  Trees. 


By  Ulendell  Paddock. 


Handling  Young  Trees: — The  writer  has  been  impressed, 
when  visiting  the  various  fruit  districts  of  the  state,  by  the  lack  of 
knowledge  on  the  part  of  many  growers  of  the  requirements  of 
young  trees.  No  doubt  a  large  majority  of  our  fruit  growers  come 
to  the  state  with  no  experience  in  the  business  and  so  have  every¬ 
thing  to  learn,  and  surely  no  part  of  orchard  management  is  more 
important  than  to  start  the  young  trees  just  right.  On  this  depends 
not  only  the  future  usefulness  of  the  orchard  but  in  many  instances 
large  numbers  of  young  trees  fail  to  live  through  the  first  season 
foAhe  simple  reason  that  the  trees  were  not  properly  started.  In 
several  instances  the  Experiment  Station  has  been  asked  to  investi¬ 
gate  the  cause  of  the  dying  of  newly  planted  trees,  and  on  visiting 
the  orchard  it  was  found  that  the  trees  were  planted  just  as  they 
had  been  received  from  the  nursery.  No  doubt  some  of  them  had 
been  injured  somewhat  by  exposure  and  improper  care  but  with  the 
best  of  treatment  it  is  difficult  for  the  mutliated  root  system  of  a 
transplanted  tree  to  establish  itself  and  at  the  same  time  support  a 
vigorous  or  overgrown  top. 

It  is  not  generally  realized  that  when  a  tree  is  taken  from  the 
nursery  row,  a  large  portion  of  the  root  system  is  left  in  the  ground. 
The  balance  between  the  roots  and  the  top  is  thus  destroyed  and 
obviously  a  part  of  the  top  should  be  removed.  Practically  all  of 
the  elements  which  nourish  and  build  up  a  tree,  save  one,  are  taken 
from  the  soil  by  the  roots  in  liquid  form.  This  material  is  carried 
in  the  cell  sap  mostly  through  the  outer  sap  wood  to  the  leaves. 
Here  the  crude  food  is  changed  by  the  influence  of  the  sun  light 
and  the  green  substance  of  the  leaves  to  a  form  that  can  be  readily 
assimilated  by  the  plant.  This  will  illustrate,  briefly,  how  impor¬ 
tant  the  roots  are  to  a  plant.  Much  of  this  elaborated  food  may  be 
stored  in  the  cells,  especially  in  the  fall,  to  be  drawn  upon  at  any 
time  that  the  roots  fail  to  supply  the  requisite  amount.  In  trans¬ 
planting,  the  nursery  tree  is  often  deprived  of  one-half  or  more  of 
its  roots,  and  not  only  must  it  become  established  in  the  soil  but  it 
must  produce  a  large  number  of  new  roots  before  much  new  food 
can  be  supplied.  In  the  meantime  the  leaves  begin  to  push  out 


4  STATE  AGRICULTURAL  COLLEGE 

and  the  reserve  food  and  moisture  may  all  be  used  before  the  root 
system  is  in  a  condition  to  supply  more. 

Is  it  any  wonder,  then,  that  the  failure  to  cut  back  the  tops  of 
newly  planted  trees  results  in  the  death  of  many  of  them  ?  This 
is  especially  true  in  Colorado  as  the  dry  air  and  intense  sunshine 
cause  the  young  trees  to  dry  out  rapidly. 

It  is  also  true  that  many  nurserymen,  as  well  as  fruit  growers, 
are  careless  in  handling  trees  before  they  are  planted.  Not  infre¬ 
quently  the  roots  are  exposed  for  hours  to  the  drying  action  of 
wind  and  sun.  One  must  take  the  chances  of  such  treatment  from 
the  nurserymen  but  after  the  trees  have  been  received  by  the  grow¬ 
er  there  is  no  excuse  for  neglect  in  this  respect.  The  trees  should 
be  heeled  in  deeply  at  once  in  damp  soil  and  when  planting  the 
work  should  be  so  arranged  that  the  roots  of  each  tree  shall  be  ex¬ 
posed  to  the  air  for  the  shortest  possible  time. 

All  bruised  and  torn  roots  should  be  carefully  removed,  leaving 
smoothly  cut  ends  which  will  readily  heal;  if  this  is  not  done  decay 
is  apt  to  set  in  which  may  seriously  injure  the  tree.  Long  strag¬ 
gling  roots  may  well  be  shortened  and  if  a  tangled  mass  of  fine 
roots  are  present  they  should  be  shortened  and  thinned.  Some 
successful  growers  also  insist  that  where  large  spreading  roots  oc¬ 
cur  a  slanting  cut  should  be  made  so  that  the  cut  surface  may 
rest  flat  upon  the  ground. 

It  would  seem  to  be  almost  superfluous  to  insist  on  the  impor¬ 
tance  of  having  all  nursery  stock  inspected  by  the  County  Inspec¬ 
tors,  yet  there  are  a  few  who  try  each  year  to  evade  the  law  in  this 
respect.  There  are  several  insect  pests  and  plant  diseases,  which 
are  very  common  on  young  trees,  all  of  which  may  be  easily  over¬ 
looked  by  anyone  who  is  not  thoroughly  familiar  with  them.  The 
wooly  aphis  is  such  an  insect  and  it  is  doing  a  great  amount  of 
damage  in  all  sections  of  the  state-.  This  insect  lives  on  the  roots 
of  trees  and  is  introduced  to  our  orchards  almost  wholly  by  infected 
nursery  stock.  When  once  established  it  spreads  rapidly  and  is  al¬ 
most  impossible  to  eradicate.  Crown  gall  is  a  common  disease  in 
many  nurseries  and  it  attacks  all  kinds  of  fruit  trees.  It  is  the 
worst  kind  of  folly  to  plant  a  tree  which  has  a  trace  of  this  disease, 
for  not  only  is  the  tree  pretty  sure  to  die  before  it  comes  into  full 
bearing  but  the  infection  may  be  spread  by  the  cultivator  or  in  the 
irrigation  water  to  all  parts  of  the  orchard.  A  statement  made  in  a 

former  bulletin  on  the  subject  of  inspection  will  bear  repetition 
here: 

.  .  AM  possible  assistance  should  be  given  the  County  Inspectors  in 
their  inspection  of  nursery  stock.  In  counties  where  many  trees  are  be¬ 
ing  planted,  sufficient  assistance  should  be  provided,  so  that  there  will  be 
no  possibility  of  any  shipments  being  overlooked.  And  finally  some 
means  should  be  devised  whereby  the  importance  of  inspection  can  be  im¬ 
pressed  on  the  growers  since,  in  some  instances,  they  antagonize  the  in- 


PRUNING  FRUIT  TREES 


5 

spectors  and  hinder  their  work.  It  is  no  doubt  true,  that  the  inspection 
of  nursery  stock  alone,  if  well  done,  pays  many  times  over  for  all  the  ex¬ 
pense  incurred,  even  in  those  counties  which  expend  the  most  money  in 
orchard  inspection.” 

But  in  those  counties  where  several  hundred  thousand  trees  are 
planted  each  spring  the  inspectors  are  so  rushed  with  their  work 
that  the  most  careful  men  are  liable  to  overlook  an  occasional  in¬ 
fected  tree;  therefore  no  grower  can  afford  to  be  unfamiliar  with 
these  common  pests.  Bach  tree  should  be  reinspected  as  it  is 
planted  and  to  make  the  work  thorough,  the  roots  should  be  dipped 
in  water  so  as  to  remove  any  dirt  which  might  conceal  small  galls 
or  a  few  aphids. 

In  this  discussion  it  is  presumed  that  the  planting  is  done  in 
the  spring  as  this  is  nearly  the  universal  practice  in  this  state. 

It  should  also  be  stated  here  that  the  requirements  of  apple 
trees  have  been  foremost  in  mind  in  the  following  pages.  The 
same  principles  will  apply,  however,  to  all  of  our  other  kinds  of  fruit 
with  the  possible  exception  of  the  peach.  A  short  discussion  of 
the  special  requirements  of  this  fruit  is  given  at  the  end  of  the  bul¬ 
letin. 

The  proper  formation  of  the  top  is  by  no  means  the  least  im¬ 
portant  reason  for  cutting  back  the  branches  of  newly  planted 
trees.  In  the  first  place  the  importance  of  low  headed  trees  for 
this  climate  cannot  be  too  strongly  emphasized.  Hundreds  of  trees 
are  dying  in  all  parts  of  Colorado  because  of  the  exposure  of  the 
long  trunks  to  the  afternoon  sun,  either  directly  or  by  reflection 
from  hot  dry  soil  in  summer  or  snow  in  winter.  Young  trees  are 
especially  liable  to  injury  which  results  in  early  death  or  a  weak, 
sickly  growth  from  which  they  never  recover.  There  is  less  injury 
from  sun  scald  in  the  humid  states,  but  in  these  districts  many 
authorities  are  advocating  lower  headed  trees. 

In  addition  to  forming  low  heads  there  can  be  no  question  but 
that  it  pays  to  still  further  protect  the  trunks  of  newly  planted  trees 
from  injury  by  sun  scald.  Various  devices  are  used,  such  as  wrap¬ 
ping  the  trunks  with  burlap,  paper,  straw,  wood  veneer,  or  by  shad¬ 
ing  the  trunk  on  the  southwest  side  with  a  thin  piece  of  board  set 
upright  in  the  ground.  Whitewashing  the  young  trunks  to  serve 
the  same  purpose  has  come  to  be  extensively  used  in  portions  of 
California.  Whatever  method  is  adopted,  it  should  be  applied  soon 
after  the  trees  are  planted  and  kept  in  good  condition  through  the 
second  winter  or  until  the  shade  of  the  trees  becomes  ample. 

The  advantages  of  low  headed  trees  may  be  mentioned  as  fol¬ 
lows:  Greater  ease  in  picking,  thinning,  pruning  and  spraying  and 
less  damage  to  trees  and  fruit  from  winds.  Some  growers  object  to 
low  headed  trees  on  account  of  the  greater  difficulty  of  cultivating 
around  them,  but  with  proper  pruning  low  headed  trees  develop  as¬ 
cending  branches  as  shown  in  plate  I.  There  is  not  the  slightest 


6  STATE  AGRICULTURAL  COLLEGE 

difficulty  in  working  around  the  trees  in  this  orchard,  whereas  the 
branches  on  high  headed  trees  commonly  droop  after  they  have 
borne  a  full  crop  of  fruit  and  so  interfere  with  all  orchard  manage¬ 
ment. 

The  following  extract  is  taken  from  Prof.  Bailey’s  Pruning 
Book: 

“The  relative  merits  of  high  or  low  heads  for  fruit  trees  are  always 
in  dispute.  This  controversy  is  partly  the  result  of  confusion  of  ideas, 
and  partly  of  differing  mental  ideals  and  of  varying  climates.  Two  fac¬ 
tors  are  chiefly  concerned  in  these  disputes — the  question  of  ease  of  culti¬ 
vation,  and  the  question  of  injury  to  the  trunk  by  sun-scald.  It  is  the 
commonest  notion  that  short  trunks  necessarily  make  low  heads,  and  yet 
any  one  who  can  see  a  tree  should  know  better.  The  number  of  trunks 
which  a  tree  has  does  not  determine  the  direction  of  the  leaf-bearing  limbs. 
This  tree  (referring  to  illustration)  can  be  worked  around  as  easily  as  it 
could  be  if  it  only  had  one  long  trunk.  In  fact,  branches  which  start  high 
from  a  trunk  are  very  apt  to  become  horizontal  and  to  droop.  There  must  be 
a  certain  number  of  scaffold  limbs  to  form  the  head.  If  these  limbs 
are  taken  out  comparatively  low,  they  may  be  trained  in  an  upright  direc¬ 
tion  and  hold  their  weight  and  position.  If  they  are  started  out  very  high 
they  will  not  take  such  an  upright  direction,  because  the  tree  will  not 
grow  beyond  its  normal  stature.  High  trained  trees  are  often  practically 
lowest  headed.” 

Form  of  Tree. — The  business  of  orcharding  is  not  old 
enough  to  have  developed  systems  of  pruning  which  may  be  said 
to  be  characteristic  of  the  state.  The  conditions  existing  in  the 
fruit  districts  have  been  so  favorable  for  the  production  of  fine  fruit 
that  the  growers  have  not  felt  the  need  of  the  finest  development 
of  the  art.  We  have  grown  fine  fruit  whether  we  would  or  no. 
But  now  that  competition  is  more  severe  and  insects  and  diseases 
are  multiplying  more  attention  must  be  given  to  methods  and  sys¬ 
tems  of  culture. 

In  pruning  trees  one  of  two  ideals  must  be  adopted,  which  are 
known  as  the  pyramidal  and  vase  forms.  The  former  preserves  the 
leader,  which  is  made  to  form  a  central  shaft  to  the  tree.  This 
style  has  the  advantage  of  more  bearing  surface,  as  the  leader  grows 
and  in  time  forms  a  “two-storied”  tree.  The  objections  to  tall  trees 
are  apparent  and  need  not  be  discussed  here.  The  leader  is  done 
away  with  in  the  vase  form  and  a  few  limbs,  usually  not  more  than 
five,  are  selected  to  form  the  top.  A  more  or  less  open  centered 
tree  is  thus  formed,  but  by  skillful  pruning  this  space  is  occupied 
by  branches  of  bearing  wood.  Very  tall  trees  are  thus  avoided,  but 
what  is  more  important,  such  trees  are  not  so  apt  to  be  destroyed  by 
blight,  as  recently  pointed  out  by  Mr.  Waite.  Death  to  trees  re¬ 
sult  when  the  blight  germs  gain  entrance  to  the  trunks  and  larger 
limbs.  Such  attacks  are  usually  brought  about  by  the  presence  of 
small  limbs,  water  spouts  or  fruit  spurs,  which  become  diseased  and 
which  the  germs  follow  till  the  main  trunk  or  branch  is  reached. 
Should  the  leader  of  a  pyramidal  tree  be  attacked  seriously  enough 
to  necessitate  its  removal  the  tree  would  be  ruined,  but  by  having 


PRUNING  FRUIT  TREES 


7 

several  main  branches  or  trunks  one  of  them  might  be  spared  with¬ 
out  seriously  crippling  the  tree.  But  the  protection  may  be  carried 
still  further  by  keeping  the  main  branches  of  the  vase  shaped  tree 
free  of  all  small  limbs  and  fruit  spurs  which  are  so  susceptible  to 

attacks  of  blight. 

Shaping  the  Newly  Planted  Tree.  —  The  term  low 
headed,  is  a  relative  one,  but  a  top  may  be  considered  low 
when  the  first  branch  is  thirty  inches  from  the  surface  of  the 
ground.  Some  of  our  successful  growers  prefer  higher  heads 
than  this,  while  others  start  them  lower.  Our  own  preference  is  for 
a  trunk  about  twenty  inches  in  height.  But  whatever  height  is  de¬ 
termined  upon,  the  tree  must  be  cut  back  preferably,  just  after  it 
has  been  planted.  Should  the  tree  be  supplied  with  suitable  limbs 
at  the  point  where  the  head  is  desired  three  to  five  of  them,  properly 
spaced,  should  be  selected  to  form  the  frame  work  of  the  tree.  The 
rest  are  removed.  The  Selected  branches  should  then  be  shortened 
in  to  a  sound  bud  within  a  few  inches  of  the  main  stem.  But  ordi¬ 
narily  the  lower  branches  are  pruned  off  in  the  nursery  so  that  we 
seldom  get  a  tree  from  which  suitable  branches  may  be  selected.  In 
this  case  the  entire  top  should  be  removed  without  regard  to 
branches,  making  the  cut  a  foot  to  eighteen  inches  above  the  point 
where  the  lowest  limb  is  wanted.  In  doing  this  it  is  expected  that 
branches  will  push  out  below  in  sufficient  numbers  so  that  suitable 
selections  may  be  made.  For  this  reason  strong  yearling  trees 
are  always  preferable  to  older  ones  and  in  fact  apple  tiees  of  this 
age  are  now  commonly  used  in  California.  Should  suitable  branches 
fail  to  grow,  one  of  the  lower  branches  which  nearly  always 

form,  must  be  developed  to  form  a  new  heady  # 

The  trees  should  be  gone  over  several  times  during  the  first 
summer  to  remove  surplus  shoots  and  especially  those  which  push 
out  far  below  the  point  where  the  lowest  branch  is  wanted.  Occa¬ 
sionally  some  of  the  upper  branches  develop  a  vigorous  growth  at 
the  expense  of  the  others.  These  should  be  headed  back  so  as  to 
give  all  a  chance  to  develop,  otherwise  some  of  the  important  scaf¬ 
fold  limbs  may  be  found  to  be  very  weak  at  the  close  of  the  season. 

When  a  branch  is  headed  back  great  pains  should  be  taken  to 
make  a  slanting  cut  just  above  a  sound  bud.  If  made  too  far  above 
the  stub  will  die  back  at  least  as  far  as  the  bud,  and  often  farther 
If  made  too  close,  the  bud  may  be  so  injured  that  a  stub  is  formed 

which  will  die  back  at  least  to  the  next  sound  bud. 

As  soon  as  the  trees  are  planted,  then  the  top  should  be  cut 
back  as  described  above.  Ordinarily  a  profusion  of  branches  will 
be  pushed  out  which  may  be  allowed  to  grow  as  they  will  during 
the  first  season  or  they  may  be  cut  back  to  one  or  two  buds.  By  the 
time  these  branches  begin  to  grow  the  roots  are  established  m  the 
soil  and  new  ones  formed  so  that  an  adequate  supply  of  plant  looc  is 


8 


STATE  AGRICULTURAL  COLLEGE 


provided.  It  will  be  remembered,  however,  that  the  plant  cannot 
use  this  food  until  it  has  been  made  over  in  the  leaves.  It  is  for 
this  reason  that  a  large  leaf  surface  is  necessary  and  it  is  also  desira¬ 
ble  m  that  the  shade  forms-  a  protection  from  the  sun. 

The  kind  of  top  which  the  tree  is  to  assume  is  developed  with 
t  le  first  season’s  pruning,  which  should  be  begun  in  most  sections 
not  earlier  than  the  first  of  March.  This  is  true  for  the  reason  if 
done  earlier  a  longer  time  must  elapse  before  the  wounds  can  heal 
and  necessarily  the  cut  surfaces  are  exposed  that  much  longer  to 
the  drying  action  of  the  sun,  wind  and  frost.  It  is  commonly 
understood  among  orchardmen  that  trees  must  not  be  pruned  when 
the  wood  is  frozen.  Pruning  when  the  trees  are  in  this  condition 
often  results  m  bad  wounds  and  the  dying  back  of  branches,  but 
this  result  is  probably  due  to  the  agencies  just  mentioned  rather 
than  to  the  fact  that  the  wood  was  frozen.  In  any  case  the  rule 
is  a  good  one  to  follow.  Then,  too,  there  is  always  more  or  less 
danger  from  winter  killing  after  early  pruning  is  done  so  that  the 
trees  would  need  to  be  gone  over  a  second  time. 

From  three  to  five  limbs  are  now  selected  to  form  the  frame¬ 
work  of  the  tree  which  should  be  cut  back  about  twelve  inches  from 
the  trunk.  The  rest  are  removed.  If  the  lowest  branch  has  been 

at  twenty  inches  from  the  ground,  the  highest  branch 
should  be  at  .east  a  foot  above;  two  feet  would  be  better.  A  com¬ 
mon  mistake  is  to  cut  trees  back  too  far  thus  crowding  the 
branches  as  shown  in  plate  I.  Neither  were  these  branches 
thinned  out  nor  headed  in  during  the  first  season  but  were  all 
allowed  to  develop  into  leaders.  This  latter  mistake  often  re¬ 
sults  m  long  willowy  branches  which  droop  with  a  load  of  fruit  and 
is  the  mam  reason  for  ’condemning  low  headed  trees.  Many  growers 
carry  their  pruning  up  to  this  point  successfully,  but  fail  to  head 

m  the  first  season’s  growth  and  so  miss  one  of  the  critical  points  in 
the  proper  formation  of  the  top.  ^ 

It  is  a  common  notion  that  the  branches  gradually  get  hio-her 
r°m  the  ground  as  the  tree  continues  to  grow.  The  apparent  gain 
eight  is  due  solely  to  the  increase  in  diameter  of  the  limbs 
w  ich  soon  begin  to  crowd  if  sufficient  space  has  not  been  left  be- 
we^n  em.  he  centers  of  the  limbs  will  always  remain  the  same 
distance  apart,  so  in  forming  the  head  one  should  have  in  mind 

what  the  appearance  of  the  limbs  will  be  when  they  have  attained 
a  diameter  of  six  or  more  inches. 

liml-TTT  Y,EAR:~It  ,may  be  reKarded  as  a  rule,  that  when  a 

s  cut  back,  unless  the  cut  is  made  just  above  a  strong  lateral 

L°  V  ,m<?re  branches  will  develop  near  the  cut  end  and  some  of 

is  to  TS  Ter  Wl11  devel°P  into  shoots-  The  usual  practice 

to  form  nViv  °f  [T6  t0  grOW  on  each  of  the  Previ°us  years  limbs 
to  form  additional  framework  for  the  tree.  The  two  selected  should 


PLATE  I.  — LOW  HEADED  TREES  WITH  ASCENDING  BRANCHES . 


PLATE  II  .—YOUNG  APPLE  TREES  WELL  HEADED  IN 


9 


PRUNING  FRUIT  TREES 

be  some  distance  apart,  one  at  the  end  and  one  farther  back,  and  so 
placed  that  the  development  of  crotches  will  be  impossible.  They 
are  now  cut  back  from  a  half  to  two-thirds  of  their  growth  and  the 
laterals  are  shortened  to  one  or  two  buds  so  that  they  may  later  de¬ 
velop  fruit  spurs  and  also  shade  the  branches  with  their  cluster  of 
leaves.  If  too  many  have  formed,  some  of  them  should  of  course  be 
removed.  On  the  other  hand  if  we  are  to  develop  Mr.  Waites’  idea 
of  making  the  tree  more  resistant  to  blight  these  laterals  should  all 
be  removed  and  so  carry  the  fruit  bearing  wood  farther  away  from 
the  trunk  and  main  branches. 

Some  growers  object  to  heading  in  trees  at  all,  for  the  reason 
that  all  of  the  buds  are  likely  to  develop  into  branches  and  so  the 
formation  of  fruit  spurs  is  retarded  and  the  surplus  branches  must 
be  cut  out.  But  it  is  highly  desirable  that  all  of  the  buds  should 
develop  and  then  by  heading  them  back  to  spurs,  as  just  mentioned, 
the  formation  of  fruit  spurs  is  largely  under  control  of  the  pruner’ 

Any  tendency  toward  one-sidedness  may  to  some  extent  be 
corrected  and  open  spaces  filled  in  by  selecting  branches  that  are  al¬ 
ready  growing  in  the  general  direction  of  the  vacancy.  Then  by 
cutting  to  a  bud,  which  is  on  the  side  toward  the  opening,  such 
faults  may  gradually  be  overcome. 

Third  Year:— The  frame  work  of  the  tree  should  now  be 
well  formed  so  that  it  will  require  less  attention  from  this  time  on. 
Surplus  branches  and  those  that  rub  or  are  inclined  to  form  crotches 

should  be  removed.  Very  vigorous  growths  should  also  be 
headed  in. 

Thus  far  out  discussion  has  been  confined  to  the  shaping  of 
open. or  vase  formed  trees.  If  a  leader  is  desired,  the  treatment  is 
practically  the  same,  except  that  the  upper  shoot  is  allowed  to  grow 
with  little  heading  in.  Branches  are  allowed  to  develop  on  this 
leader  at  proper  intervals,  using  the  same  care  as  to  location,  prun¬ 
ing  and  development  as  in  the  former  case. 

A  discussion  of  some  photographs  of  actual  experience  in  prun¬ 
ing  young  trees  will  help  to  review  and  fix  the  points  of  the  differ¬ 
ent  stages  of  pruning  in  mind.  These  were  second  grade  trees  and 
were  evidently  three  years  old  when  planted.  The  lower  laterals 
had  all  been  pruned  away  in  the  nursery  so  that  the  tops  were  much 
too  high  for  Colorado.  There  was  also  difficulty  in  getting  branches 
to  form  at  suitable  places  from  which  to  make  the  selections  for  the 
head.  However,  the  results  are  much  better  than  as  though  the 
tops  had  been  left  as  received  from  the  nursery  as  is  so  often  done. 

The  trees  in  figures  i,  2  and  3  were  all  headed  back  to  about 
24  inches  in  April,  1904.  This  left  them  mere  stubs.  Had  ther? 
been  any  laterals  below  this  point  they  would  have  been  pruned 
back  to  single  buds  so  that  clusters  of  leaves  might  have  formed 
and  thus  provided  some  shade  for  the  trunks.  These  pictures  show 


IO 


STATE  AGRICULTURAL  COLLEGE 


how  the  trees  looked  in  April,  1905,  ^ie  ^me  the  first  prun¬ 
ing.  No.  i  had  formed  five  vigorous  branches,  No.  2  produced  tour 

and  No.  3  but  two. 

The  five  branches  on  No.  i  were  saved  to  form  a  framework  tor 
the  tree  and  were  cut  back  to  about  one  foot  in  length.  These  are 
well  distributed  about  the  trunk,  but  have  the  fault  that  they  are 
too  close  together.  The  lowest  limb  might  well  be  double  the  dis¬ 
tance  from  the  top  that  it  now  is.  No.  ia  shows  No.  i  after  it  was 
pruned,  with  the  idea  of  making  an  open-centered  tree. 


No.  2  is  also  open  to  the  objection  that  the  limbs  are  too  close. 
All  of  these  were  saved  to  form  the  frame  work  of  a  tree  with  a 
leader  as  is  shown  in  No.  2a.  The  only  difference  between  this  and 
No.  ia  being  that  the  topmost  branch  was  left  longer  than  the 
others.  The  pruner  of  this  tree  is  open  to  severe  criticism  m  that 
he  has  allowed  three  vigorous  limbs  to  grow  from  near  the  surface 
of  the  ground.  These  limbs  could  serve  no  useful  purpose  and  so 
only  rob  the  other  limbs  of  plant  food.  Such  growths  are  best  pre¬ 
vented  by  pinching  off  the  buds  early  in  the  season. 

No.  3  failed  to  throw  out  enough  branches  to  form  a  suitable 
top.  The  two  which  were  produced  are  nearly  opposite,  so  that  a 
bad  crotch  would  soon  result.  Both  branches  were  cut  back  to  the 
second  bud,  as  shown  in  3a,  in  the  hopes  of  inducing  dormant  buds 
to  push  out  lower  down. 


PRUNING  FRUIT  TREES 


II 


No.  4  shows  one  of  this  lot  of  trees  that  was 
left  unpruned.  Notice  the  weak  spindling  growth 
and  short  laterals  as  compared  with  the  others. 
There  is  small  chance  of  making  a  decent  tree 
out  of  such  a  specimen  even  though  it  should  live. 
Such  illustrations  as  this,  which  may  be  seen  on 
every  hand,  should  prove  to  any  one  that  all  trees 
should  be  headed  back  when  planted,  if  for  no  other 
purpose  than  to  induce  a  vigorous  growth. 

At  the  close  of  the  season  of  1905  the  pruned 
trees  had  made  a  growth  respectively  as  shown  in 
ib,  2b  and  3b. 

Pruning  should,  of  course,  be  done  in  late 
winter  or  early  spring,  but  these  trees  were  pruned 
for  the  purpose  of  illustration  and  the  results  are 
shown  in  ic,  2c  and  3c.  Tree  No.  1  has  now 
taken  the  form  shown  in  ic.  One  of  the  scaf¬ 
fold  limbs  seemed  superfluous  so  it  was  removed  and 
the  new  growth,  shown  in  Fig.  ib,  was  cut  back 
about  one-half.  The  few  side  shoots  were  cut  back 
to  a  single  bud  with  the  idea  of  developing  fruit 
spurs.  During  the  season  of  1906  numerous  branches 
should  develop  on  all  of  these  scaffold  limbs.  As  a 
rule  two  of  the  best  placed  of  these  secondary  limbs 
will  be  selected  on  each  of  main  scaffold  limbs  to  form 
additional  framework.  The  rest  may  be  removed  or 
cut  back  to  develop  fruit  spurs  as  may  se 


FKJ.  2 


FIG  2 A 


FIG.  2 B 


FIG.  2C 


I  2 


STATE  AGRICULTURAL  COLLEGE 


The  form  of  the  tree  then,  should  be  developed  at  the  beginning 
of  the  season  of  1907  and  subsequent  pruning  should  be  directed  to¬ 
ward  retaining  this  shape,  cutting  back  excessive  growths  and  thin¬ 
ning  and  renewing  the  bearing  wood. 

The  pruning  of  tree  No.  2  is  much  the  same,  except  that  a 
leader  is  being  developed.  Fig.  2c  shows  that  although  the  top 
was  cut  back  the  same  as  Tree  No.  1,  the  topmost  branch  is  devel¬ 
oping  into  a  vigorous  central  shaft.  The  first  set  of  scaffold  limbs 
have  been  formed  and  a  second  set  is  to  be  developed  at  a  suitable 
distance  above.  The  new  growth  is  to  be  cut  back  the  same  as  has 
been  described. 


The  tree  shown  in  the  series  3-3C  is,  so  far,  pretty  much  of  a  fail¬ 
ure.  The  severe  heading  given  it  in  the  spring  of  1905  failed  to  make 
branches  develop  lower  down.  It  would  have  been  a  better  plan  to 
have  inserted  two  or  three  buds  at  suitable  points  around  the  main 
stem  in  June,  1905.  This  can  probably  be  done  next  June,  but  the 
chance  for  success  is  not  so  great.  Limbs  can  be  developed  by  this 
means  just  where  they  are  wanted,  but  the  average  person  will  suc¬ 
ceed  better  with  trees  which  do  not  require  such  manipulation. 

Pruning  Bearing  Trees. — The  form  of  the  young  tree 
should  be  well  established  after  the  third  season.  From  this  time 
on  the  question  of  pruning  is  simply  to  retain  so  far  as  possible  the 


SI  ATE  AGRICULTURAL  COLLEGE 

form  we  have  started,  to  prevent  the  formation  of  crotches  and  ero« 
branches,  to  thin  out  an  excess  of  branches  so  that  sunhlfef  „  u 
admitted  and  the  amount  of  bearing  wood  reduced  and  refewed 

companying  ^i^fr^^ 

whii  S 

.biS'to  nss  sho',.^', ;'r„are  “eiy 

arise,  the  following  should  be  borne  in  mind:  Prune  in  summer  to 
nduce  fruitfulness  and  in  winter  to  promote  wood  growth  This 

tree1  hv50/  ^  r6aS°n  that  summer  Pmniug  checks  theSgrowth  of  the 
y-liT°Vm?  a  P°rtl0n  0f  the  leaf  surface.  An  injury  of  anv 
tree  r  m  tVe  16  Same  eiTect’  likewise  a  weak  growing  or  s  ck h 

in  whik  sti"  d<™ » »- 

given  as  each  tree  prLntTa  dSel^robta'”' ihick  g'romh  of 
branches  results  m  weak  bearino-  shoots  and  snnrs  a  ^  n  11 
when  cutting  back  limbs  on  bearing  trees  the  cut  shoufd  be  m  ^ 
just  above  a  strong  lateral  wherever  possible.  The  tendency  of  the 
sap  will  be  to  flow  into  the  lateral  and  thus  prevent  the  format  o„ 

sssr*" which  ”“iy  ai™>"  “"«>  *  -ss 

long IXta^S  Sch’Sl'ytnd'  A’Z  X  “ 

oir t'*  11‘e 3«S  S?  tbhTwSe'°Sap'aare 

overbear  periodically  as  they  get  older,  often  to  rod,  an  eSnuhS 
branches  are  broken  down  with  a  load  of  undersized  fruit  It 

bearinjbutrtie^fh8  !T°  “fr,0"*  t0  reC°Ver  from  the  effect  of  °ver- 
n  a  •  .  Ut  ^ e  year  the  process  may  be  repeated  A  severe 

SeT  h  and  .thin?inS  out  of  the  branches  would  largek  correct 
of  fine  fruit  “  P°SSible  f°r  the  trees  to  bear  “n«a>  crops 

growfh  of°diffi°Ufd  wel1  acquainted  with  the  habit  of 

growth  of  different  varieties  as  a  few  kinds  grow  slowly  and  will 

spreading  ^Onecau'A  °th.e[S  are.erect  growers  and  some  are 
but  Hip  g  *  1,  caunot  expect  to  entirely  overcome  such  tendencies 
but  they  may  be  corrected  to  a  marked  degree.  The  upright  varie! 

theSspreadingPkread  SOmewbat  by  Pruning  to  the  outside  laterals  and 
e  spreading  kinds  may  be  contracted  by  cutting  to  those  which 

ave  an  inward  direction.  And  by  cutting  back  the  vigorous  growths 

stockjTthus' it^erea^n  ***  ^  0Ver  “  length’  the  K"lbs  are  made 

stocky  thus  in  great  measure  doing  away  with  drooping  branches 
However,  we  believe,  that  under  our  conditions,  it  iSP  advantageous 


*4 


PRUNING  FRUIT  TREES 


in  many  ways  to  keep  trees  from  becoming  very  tall  Tus  can 
he  done  bv  intelligent  annual  pruning.  In  Plate  11.  is  snown 
a  photograph  of  a  successful  young  Colorado  orchard  that  has  been 

severely  head  discussion  has  had  to  do  entirely  with  apple  trees. 
The  same  princes  apply  to  most  of  the  other  fruits  with  the  ex- 
firm  of  those  like  the  peach  which  bear  fruit  on  last  season  s 
cepH  The  oear  is  pruned^nuch  the  same  as  the  apple,  as  are  also 
ST  Mu  “  The  latter  should  be  headed  lower 

ll*  tLv  reouire  much  less  attention  after  the  character  of  the  top 
has  been  formed.  The  sour  cherry  and  red  or  cultivat ed  varieties 
of  American  plums  require  almost  no  pruning.  The  tops  sho 

be  very  low. 

Pruning  the  Peach.— Peaches  are  borne  on  wood  of  the  pre- 
j  •  p.  vear’s  growth  consequently  the  training  from  the  beginning 
should  be  somewhlt  different  from  that  given  our  other  common 
fruit  trees  The  importance  of  peach  growing  m  the  state  will  war¬ 
rant  a  brief  description  of  methods  of  training  and  pruning. 

We  must  have  the  tops  low,  twelve  to  eighteen  inches  o  clea 
imnV  being  ample.  In  fact  the  trees  m  some  of  our  best  orchards 
are  headed  lust  above  the  surface  of  the  ground.  For  tins  reason 
medium  sized,  well  grown  yearling  trees  are  always  Parable  to  two 

yeai  ate  trees’ are  nearly  Always  cut  off  from  the  lower  portion  in 
the  nursery  so  that  it  is  rarely  possible  to  make  branches  grow 

where  theyf  are  ^wanted  £ea(h  g  ^  ^  .g  pro^ded  with  suitable 

laterals  for  forming  a  top.  As  soon  as  the  tree  is  planted,  cut  the 
too  back  to  from  twenty  four  to  thirty  inches  from  the  ground. 
Then  reduce  all  of  the  laterals  to  spurs  of  from  one  to  three  buds. 
Manv  of  the  remaining  buds  will  soon  start  into  active  grow 
S  a  large  number  5  small  shoots  result.  The  foliage  wi  l  not 
S v  orotect  the  trunk  from  the  sun  but  a  large  leaf  surface  is 
necessary  for  the  preparation  of  plant  food.  The  second  spring 
tf  i  the  trees  receive  their  first  pruning  and  the  forma- 

t'  el,!f  the  too  begins  Select  from  three  to  five  of  the  strongest 
and  best  placed  branches  to  form  the  frame  work.  If  the  lowest  one 
is  fifteen  mches  above  ground  the  upper  one  may  well  be  twelve  to 
teen  inches  higher.  The  intervening  ones  should  be  well  space  e- 
Jween and symmetrically  arranged  around  the  Stan  so  that  therein 

be  no  open  spaces,  one-sidedness  or  crotches.  T  >  ,  . 

ter  how  vigorous  their  growth  may  have  been,  should  be  cut  back 
a  half  or  two-thirds  of  their  length,  while  all  of  the  rest  are  remove 
entirely  By  making  these  main  limbs  short  they  become  stout 
and  stocky  and  the  load  of  the  matured  top  is  borne  close  to  the  ce  - 
tral  trunk  so  that  the  strain  is  materially  lessened. 


STATE  AGRICULTURAL  COEEEGE 

heiVwTi'l the  nUEery  ‘f,6  'f  lacki«g  in  laterals  at  the  proper 
W|ht  Tf  fl  Pi  St  r  cut,back  anyway  if  we  ale  to  have  a  low 
J;be !°wel:  laterals  have  been  pruned  away  in  the  nursery 
ere  will  be  difficulty  in  securing  branches  from  which  a  well  bal- 

anced  head  may  be  formed.  One  must  take  this  risk.  Should 
suitable  branches  appear  they  are  headed  in  as  above.  If  no  branches 
at  all  are  pushed  out  where  wanted,  or  those  that  are  formed 
are  so  situated  as  to  make  the  tree  very  much  one-sided,  a  branch 
from  near  the  surface  of  the  ground  will  nearly  always  develop 
which  can  be  used  to  form  a  new  trunk  and  top.  This  should  be 

treated  the  same  as  a  newly  planted  tree  and  in  three  or  four  years 
it  cannot  be  told  from  the  rest.  J 

During  the  second  and  third  years  the  pruning  and  trimming 
does  not  differ  materially  from  that  already  described.  The  laterals 
should  not  be  too  thick,  but  enough  should  be  left  to  produce  a 
good  bearing  surface  low  down.  The  trees  should  be  pruned  each 
year  from  now  on,  heading  in  the  main  branches  and  vigorous  lat¬ 
erals  from  a  half  to  two-thirds  of  their  growth  and  thinning  out 
laterals  where  too  thick.  Always  head  back  to  a  good  lateral  where- 
ever  possible  and  so  prevent  the  growth  of  surplus  shoots.  In  any 
case  short  branches  should  be  encouraged  to  grow  low  down  on  the 
trunk  and  branches  to  provide  protection  from  the  sun. 

It  is  a  mistake  not  to  keep  the  branches  on  peach  trees  well 
cut  back,  for  if  this  is  not  done  and  the  laterals  which  produce  the 
bearing  wood  grow  farther  from  the  body  of  the  tree  each  year 
which  finally  results  m  long,  bare  branches  with  a  tuft  of  bearing 
wood  at  the  end.  Neither  should  the  attempt  be  made  to  cut  the 
branches  back  evenly  all  around  the  tree,  but  each  branch  should 
be  considered  as  a  separate  problem. 

Should  trees  become  too  tall  to  be  handled  to  advantage  new 
tops  can  be  secured  by  cutting  back  all  of  the  limbs  at  the  time  the 
pruning  is  usually  done.  A  luxuriant  growth  will  push  out  from 
these  stubs  so  that  but  two  seasons  of  fruit  bearing  will  be  lost. 

Precaution  needs  to  be  taken,  however,  not  to  cut  off  too  large 
limbs,  especially  on  old  trees.  Neither  should  a  small  limb  be  cut 
back  too  close  to  its  junction  with  a  large  limb.  Perhaps  the  best 
results  will  follow  if  none  of  the  limbs  are  larger  than  two  inches 
in  diameter  at  the  point  where  the  cut  is  made.  The  stubs  should 
be  left  from  about  two  to  four  feet  in  length,  depending  upon  the 
age  of  the  tree,  the  size  of  the  limb  and  its  location.  Too  severe 
heading  in  may  easily  result  in  the  death  of  the  tree. 


I 


Bulletin  107. 


February,  1906. 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College. 


PEACH  MILDEW 


By  O.  B.  WHIPPLE 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
Fort  Collins,  Colorado. 

1906. 


THE  AGRICULTURAL  EXPERIMENT  STATION, 


FORT  COLLINS,  COLORADO. 


THE  STATE  BOARD  OF  AGRICULTURE. 


Hon.  P.  F.  SHARP,  President , 
Hon.  HARLAN  THOMAS, 

Hon.  JAMES  L.  CHATFIELD, 
Hon.  B.  U.  DYE, 

Hon.  B.  F.  ROCKAFELLOW 
Hon.  EUGENE  H.  GRUBB, 
Hon.  A.  A.  EDWARDS, 
Hon.  R.  W.  CORWIN, 


TERM 


Denver 

EXPIRES 

-  1907 

Denver,  - 

■  1907 

Gypsum,  - 

-  1909 

Rockyford, 

-  1909 

Canon  City, 

1911 

Carbondale, 

-  1911 

Fort  Collins 

,  1913 

Pueblo 

1913 

Governor  JESSE  F.  McDONALD,  \  nflinn 
President  BARTON  O.  AYLESWORTH,  \ 


A.  M.  HAWLEY,  Secretary  EDGAR  AVERY,  Treasurer 


Executive  committee  in  charge. 

P.  F.  SHARP,  Chairman.  B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS. 


Station  staff. 


L.  G.  CARPENTER,  M.  S.,  Director 
C.  P.  GILLETTE,  M.  S.,  - 

W.  P.  HEADDEN,  A.  M.,  Ph.  D.,  - 

W.  PADDOCK,  M.  S., 

W.  L.  CARLYLE,  M.  S., 

G.  H.  GLOVER,  B.  S.,  D.  V.  M., 

W.  H.  OLIN,  M.  S., 

R.  E.  TRIMBLE,  B.  S., 

F.  C.  ALFORD,  M.  S., 

EARL  DOUGLASS,  M.  S.,  - 

A.  H.  DANIELSON,  B.  S.,  - 

S.  ARTHUR  JOHNSON,  M.  S.,  - 

B.  O.  LONGYEAR,  B.  S., 

J.  A.  McLEAN,  A.  B.,  B.  S.  A., 

E.  B.  HOUSE  - 

O.  B.  WHIPPLE,  B.  A., 

P.  K.  RLTNN,  B.  S.,  -  -  Field 


-  Irrigation  Engineer 

. Entomologist 

Chemist 

Horticulturist 

. Agriculturist 

Veterinarian 
Agronomist 
Assistant  Meteorologist 
Assistant  Chemist 
Assistant  Chemist 
Assistant  Agriculturist 
Assistant  Entomologist 
Assistant  Horticulturist 
Animal  Husbandman 
Assistant  Irrigation  Engineer 
Assistant  Horticulturist 

Agent,  Arkansas  Valley,  Rockyford 


OFFICERS. 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S., . Director 

A.  M.  HAWLEY,  -  . Secretary 

MARGARET  MURRAY  ....  stenographer  and  Clerk 


PEACH  MILDEW. 


By  O.  B.  WHIPPLE. 


The  phenomenal  growth  of  the  peach  industry  in  that  part  of 
Colorado  west  of  the  Continental  Divide  is  due,  to  a  certain  extent, 
at  least,  to  the  absence  of  insect  pests  and  fungus  diseases.  While 
it  is  probable  that  our  growers  will  never  have  the  large  array  of 
these  pests,  which  are  common  in  many  other  regions,  to  contend 
with,  we  cannot  hope  to  be  entirely  immune  from  such  attacks. 
From  a  business  standpoint,  then,  we  should  be  constantly  on  the 
lookout  for  anything  in  the  nature  of  a  pest,  so  that  it  may  be 
studied  and  means  devised  for  its  control  before  its  attacks  become 

serious. 

Peach  mildew  has  made  its  appearance  in  a  few  orchards  and 
appears  to  be  spreading.  While  no  great  amount  of  damage  has 
yet  been  done,  some  of  the  growers  are  beginning  to  spray  their 
trees  for  the  control  of  the  disease. 

It  is  the  purpose  of  this  Bulletin  to  point  out  the  nature  of  the 
disease  and  describe  some  of  the  means  of  combating  it  which  have 
been  used  in  other  states.  The  Experiment  Station  has  had  no 
opportunity  as  yet  to  conduct  experiments  of  this  kind,  but  there  is 
no* reason  to  suppose  that  these  remedies  will  fail  in  Colorado  if 
properly  made  and  applied. 

The  injury  in  Colorado  is  due  to  a  fungus  which  attacks  leaves, 
twigs  and  fruit  alike.  It  appears  on  the  fruits  while  they  are  yet 
small  and  immature,  often  causing  them  to  fall  prematurely.  Its 
first  appearance  is  indicated  by  a  musty  or  frost-like  patch  upon  the 
surface.  When  well  established,  the  spots  become  almost  pure 
white;  the  color  being  due  to  the  mycelium  and  its  fruiting 
branches,  which  overrun  the  surface  upon  which  the  fungus  estab¬ 
lishes  itself.  The  flesh  of  the  fruit  becomes  hard  under  these  spots 
and  the  skin  takes  on  a  brown  or  dead  color.  The  appearance  upon 
the  twig  is  very  much  the  same,  it  being  very  conspicuous  as  white 
blotches  along  the  twigs;  the  underlying  bark  becoming  chy  anc 
brown.  Where  the  attack  is  very  severe  the  leaves  fall,  the  bark  be¬ 
comes  shriveled,  and  the  young  tips  often  assume  a  curved  position.  It 


4 


STATE  AGRICULTURAL  COLLEGE 


PLATE  I. -SHOWING  PEACH  ATTACKED1  BY  MILDEW. 


PLATE  II.— PEACH  TWIGS  ATTACKED  BY  MILDEW. 


PEACH  MILDEW 


5 


only  appears  on  the  current  year’s  growth,  it  being  able  to  establish 
itself  upon  the  more  tender  growing  parts  only.  On  the  leaves,  it 
generally  appears  upon  the  under  surface,  most  prominently  along 
the  midrib  as  white,  irregular  blotches.  The  attack  is  not  confined 
to  the  under  surface  of  the  leaf,  but  is  found  there  more  often,  proba¬ 
bly  because  strong  sunlight  is  its  worst  enemy.  The  leaves  become 
crimpled  and  curled,  the  younger  ones  near  the  tip  often  falling 
during  severe  attacks.  The  tissues  of  the  leaf  are  deadened,  and  it 
folds  more  or  less  along  the  midrib,  the  upper  surface  folding  upon 
itself. 

Attacks  of  this  fungus  often  injure  the  fruit,  in  some  cases  al¬ 
most  ruining  the  crop  for  market.  The  young  twigs  are  checked  in 
their  growth,  and  sometimes  killed  outright,  while  the  foliage  is 
greatly  reduced.  If  no  injury  to  the  crop  is  experienced  during  the 
season  of  attack  it  is  no  doubt  true  that  the  future  crops  and  good 
health  of  the  tree  are  at  stake.  Fruit  buds  for  the  coming  year 
cannot  be  developed  on  half-dead  twigs  poorly  nourished  by  a  scant 
supply  of  foliage.  Neither  is  the  tree  in  shape  to  withstand  other 
troubles  to  which  the  unhealthy  peach  tree  falls  heir. 

As  preventive  measures,  several  of  more  or  less  importance 
can  be  mentioned.  As  the  fungus  thrives  best  in  a  warm,  moist 
and  shaded  location,  anything  that  will  overcome  these  conditions 
might  be  classed  as  a  preventive.  Too  close  planting  is  not 
recommended,  as  in  such  plantations  a  free  circulation  of  air  is  shut 
off.  Pruning  to  an  open  head  would  no  doubt  be  an  advantage  in 
favor  of  the  tree.  In  other  words,  plant  and  prune  the  orchard  to 
favor  a  free  circulation  of  air  and  plenty  of  sun  about  and  on  the 
inside  of  the  tree.  Experience  with  other  mildews  would  seem  to 
suggest  that  as  a  preventive  measure,  a  cool  soil  and  location  be 
selected.  Some  have  recommended  the  planting  of  varieties  that 
seem  to  be  free  from  attack,  but  in  this  state  little  or  no  preference 
has  been  shown  by  the  fungus  for  certain  varieties.  The  statement 
has  been  made  that  the  disease  seemed  to  be  restricted  to  the  ser¬ 
rate,  glandless-leaved  varieties,  but  in  three  lots  of  infested  ma¬ 
terial  sent  in  to  the  Station  by  fruit  growers  of  the  state  two  had 
serrate  leaves  and  very  conspicuous  glands,  while  the  third  was 
serrate,  glandless.  It  has  been  noticed  that  it  is  especially  bad  on 
seedlings  in  infested  localities.  It  seems  hardly  necessary  to  take 
out  infested  trees  as  some  have  recommended,  but  no  doubt  the 
seedlings  above  mentioned  could  be  disposed  of  at  little  loss  to 
the  grower  and  may  noticably  check  the  spread  of  the  disease. 

No  extensive  experimental  work  has  been  followed  out  along 
the  lines  of  determining  remedies  for  this  disease;  nevertheless, 
knowing  its  habit  of  growth  and  the  action  of  the  various  sprays 
upon  the  peach,  no  fear  is  entertained  in  recommending  a  system 


6 


STATE  AGRICULTURAL  COLLEGE 


of  spraying  which  will  no  doubt  prove  effective  in  holding  peach 
mildew  in  check. 


In  his  “Fruits  of  California”  Wickson,  on  the  subject  of  com¬ 
bating  mildew  says: 

“This  has  been  effectually  done  by  thorough  sulphuring.  Mr.  Klee 
advises  three  applications  where  mildew  is  apt  to  be  bad ;  the  first  one 
very  early  in  the  season.” 


Owing  to  the  smooth  surface  of  the  foliage  of  the  peach  such 
applications  would  necessarily  have  to  be  made  early  in  the  morn¬ 
ing  or  after  a  rain,  while  the  foliage  is  damp.  Though  the  applica¬ 
tion  is  generally  a  very  simple  matter  when  the  dust  sprayer  is  at 
hand,  it  will  not,  as  a  rule,  prove  as  satisfactory  as  other  methods. 

Lodeman,  in  his  “Spraying  of  Plants,”  says: 


“It  is  probable  that  the  disease  can  be  held  in  check  by  spraying  the 
trees  with  Bordeaux  Mixture  as  soon  as  the  fruit  has  set,  and  follow  this 
at  intervals  of  two  weeks  by  two  treatments  of  one  ounce  of  carbonate  of 
copper  dissolved  in  ammonia  and  diluted  with  twelve  gallons  of  water.” 

Peach  mildew  being  a  surface  grower  there  is  no  reason  why  any 
of  our  standard  fungicides  might  not  be  employed  in  fightingit.  A  tlior 
ougli  spraying,  before  the  trees  come  into  bloom,  with  formula  A  or 
C,  is  recommended.  After  the  blossoms  have  fallen  ,  an  application 
of  B  or  D  should  be  made.  Follow  this  at  intervals  of  ten  days  or 
two  weeks  with  one  or  two  more  applications  of  B  or  D.  While  A 
and  E  are  sometimes  recommended  for  use  on  the  peach  while  the 
tree  is  in  full  leaf  they  are  liable  to  burn  the  foliage  more  or  less, 
and  though  it  may  not  prove  dangerous  to  the  life  or  health  of  the 
tree,  it  is  well  to  give  up  their  use  for  others  that  are  safe  as  well  as 
efficient.  Formula  B  is  a  modification  of  the  regular  Bordeaux  mix- 
ture  sometimes  recommended  for  the  peach,  and  can  be  safely  used 
upon  the  peach  during  the  growing  period.  Formula  E  is  a  very 
safe  and  effective  spray  for  the  first  application  before  the  leaves 
come  out,  but  others  given  are  much  more  simple  in  preparation  and 
just  as  effective. 


Formula  A. 


-Bordeaux  Mixture.  - 

Copper  sulphate  (Blue  stone  or  Blue  vitriol),  4  lbs. 

Quick  lime  . . . . . . . . . . . 4  lbs. 

Water  . . . . . . 45  gal. 


Formula  B.— Copper  sulphate..... . 2  lbs. 

Quick  lime.  .  ' . 4  lbs 

Water  . 45  gal. 

Formula  C. — Copper  sulphate . 1  lbs. 

Water . 25  gal. 

Formula  D.— Copper  sulphate . 1  lb. 

Water . 400  gal. 


Formula  E.— Copper  carbonate . 1  oz. 

Ammonia  (enough  to  disol ve  copper  carbonate.) 
Water . 12  gal. 

The  effectiveness  of  any  of  these  sprays  depends  upon  the 


PEACH  mildew 


7 


thoroughness  with  which  it  is  applied,  and  pains  should  betaken  to 
reach  all  parts  of  the  tree.  A  nozzle  that  breaks  up  the  spray 
well  will  save  much  time.  Fresh  unslacked  lime  only  should  be  used. 
It  should  be  slacked  in  water  in  a  separate  vessel  diluted  to  a  thin 
whitewash  and  strained  through  one  or  two  thicknesses  of  burlap 
or  sacking,  or  through  a  strainer  with  openings  the  size  of  a  pin 
head,  before  using.  This  prevents  the  clogging  of  the  nozzles  v\ith 
any  of  the  coarse  material  left  after  slacking.  The  copper  sulphate 
should  be  dissolved  in  warm  water  if  wanted  for  immediate  use. 
It  may  be  dissolved  in  a  considerable  quantity  of  cold  water  by 
suspending  it  in  a  sack  just  beneath  the  surface.  If  to  be  used  in 
large  quantities  it  is  well  to  make  up  a  stock  solution  by  dissolving 
fifty  pounds  in  twenty-five  gallons  of  water.  Keep  well  covered  to  pre¬ 
vent  evaporation.  Two  gallons  of  this  solution  contains  the  four 
pounds  of  copper  sulphate  called  for  in  formula  A,  or  one  gallon 
contains  the  two  pounds  called  for  in  formula  B.  The  required 
amount  of  this  solution  should  be  diluted  to  at  least  thirty  gallons 
before  the  lime  water  is  added.  The  lime  may  be  slacked  in  large 
quantities,  in  which  condition  it  will  keep  well  all  summer,  and  the 
amount  of  lime  water  or  paste  required  may  be  determined  by  a 
chemical  test. 

For  this  test  potassium  ferro- cyanide  may  be  secured  of  any 
druggist  and  prepared  for  use  by  dissolving  in  ten  times  its  bulk  of 
water.  A  quantity  of  lime  water  is  then  added  to  the  diluted  cop¬ 
per  solution,  stirred  well  and  a  drop  of  cyanide  dropped  upon  the 
surface.  If  it  gives  a  reddish  brown  color  to  the  mixture,  more  lime 
must  be  added  and  the  test  repeated  until  no  reaction  occurs.  This 
indicates  that  all  harmless  acids  of  the  copper  have  been  neutralized 
and  the  mixture  is  ready  for  use.  Red  litmus  paper  may  be  used 
and  lime  added  until  the  solution  turns  the  paper  to  a  blue  color. 

Bordeaux  mixture  deteriorates  rapidly  and  should  be  used  as 
soon  as  prepared.  While  being  sprayed  it  requires  constant  stir¬ 
ring.  In  the  preparation  of  the  mixture  no  metal  vessels  or  tool 
other  than  copper  or  brass  should  be  used. 


Bulletin  108. 


March,  1906. 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College. 


Development  of  the 
Rockyford  Cantaloupe  Industry. 


PHILO  K.  BLINN. 

I 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
FORT  COLLINS,  COLORADO 

1906 


The  Agricultural  Experiment  Station, 

FORT  COLLINS,  COLORADO. 


THE  STATE  BOARD  OF  AGRICULTURE.  Te 

Expires 

Hon.  P.  F.  SHARP,  President , . Denver.  1907 

Hon.  HARLAN  THOMAS, . Denver.  1907 

Hon.  JAMES  L.  CHATFIELD, . Gypsum.  1909 

Hon.  B.  U.  DYE, . Rocky  ford.  1909 

Hon.  B.  F.  ROCKAFELLOW . Canon  City.  1911 

Hon.  EUGENE  H.  GRUBB, . Carbondale.  1911 

Hon.  A.  A.  EDWARDS, . Fort  Collins.  1913 

Hon.  R.  W.  CORWIN,  -  - . Pueblo.  1913 


Governor  JESSE  F.  McDONALD, 
President  BARTON  O.  AYLESWORTH, 


ex-officio . 


A.  M.  HAWLEY,  Secretary.  EDGAR  AVERY,  Treasurer. 


Executive  Committee;  in  Charge. 

P.  F.  SHARP,  Chairman. 

B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS. 


STATION  STAFF. 

L.  G.  CARPENTER,  M.  S.,  Director,  -  -  -  Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S., . Entomologist 

W  P.  HEADDEN,  A.  M.,  Ph.  D.,  . Chemist 

WENDELL  PADDOCK,  M.  S., . Horticulturist 

W.  L.  CARLYLE,  M.  S.,  . -  Agriculturist 

G.  H.  GLOVER,  B.  S.,  D.  V.  M.,  ------  Veterinarian 

W.  H.  OLIN,  M.  S.,  -  -  .  -  -  -  -  -  -  -  *  Agronomist 

R  E.  TRIMBLE,  B.  S., . Assistant  Meteorologist 

F '  C.  ALFORD,  M.  S., . Assistant  Chemist 

EARL  DOUGLASS,  M.  S., . Assistant  Chemist 

F.  KNORR,  . . Assistant  Agriculturist 

s’  ARTHUR  JOHNSON,  M.  S  ,  -  Assistant  Entomologist 

■r  o  LONGYEAR.  B.  S.,  - . Assistant  Horticulturist 

j.‘  A.  McLEAN,  A.  B.,  B.  S.  A., . Animal  Husbandman 

E.  B.  HOUSE,  B.  S.,  -  -  -  -  Assistant  Irrigation  Engineer 

O.  B.  WHIPPLE,  B.  S.,  -  -  -  -  -  -  Assistant  Horticulturist 

P.  K.  BLINN,  B.  S.,  -  -  Field  Agent,  Arkansas  Valley,  Rockyeord 

Western  Slope  Fruit  Investigations,  Grand  Junction: 

. -  Field  Horticulturist 

ESTES  P.  TAYOR,  B.  S., . Field  Entomologist 


Officers. 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S.,  -  -  -  -  -  -  Director 

A.  M.  HAWLEY. . Secretary 

MARGARET  MURRAY, . Stenographer  and  Clerk 


Development  of  the  Rockyford  Cantaloupe 

'  Industry. 

Philo  K.  Blinn. 


HARDY  HISTORY. 

Rockyford  Netted  Gem  Cantaloupes  have  been  produced  in 
the  vicinity  of  Rockyford  for  about  twenty  years,  while  other  va¬ 
rieties  of  cantaloupes  or  muskmelons  are  reported  as  having  been 
grown  at  an  earlier  period  by  the  first  settlers  along  the  valley. 

The  honor  of  growing  the  first  Rockyford  cantaloupes  for 
market  is  accredited  to  Mr.  J.  W.  Eastwood  now  a  resident  of 
Phoenix,  Ariz.  The  same  season  Mr.  J.  E.  Gauger,  a  few  miles 
west  of  La  Junta  also  grew  a  small  patch  of  the  Netted  Gems 
from  seed  secured  from  Mr.  W.  Atlee  Burpee  who  introduced  the 
Variety  in  1881. 

Mr.  Eastwood  relates  the  beginning  of  the  industry  in  the 
following  narrative : 

I  removed  from  Denver  to  Rockyford  in  November,  1884,  and  as  I 
had  previously  been  growing  the  Netted  Gem  cantaloupes,  I  determined  to 
try  them  there.  Accordingly  the  following  spring,  I  planted  about  one- 
half  acre,  and  so  far  as  I  know,  this  was  the  first  of  this  variety  grown 
at  Rockyford.  Mr.  G.  W.  Swink  was  growing  a  larger  variety,  but  after 
making  several  close  inspections  of  the  Netted  Gems  as  he  saw  them  grow¬ 
ing  during  the  season,  said  he  was  convinced  that  they  were  the  canta¬ 
loupes  to  grow. 

He  selected  a  dozen  or  so  for  seed  which  were  the  first  of  this  variety 
in  Rockyford  to  be  saved  for  seed.  I  secured  my  seed  either  through  Mi*. 
Henry  Lee  of  Denver  or  Mr.  Burpee  of  Philadelphia. 

At  that  time  no  thought  was  given  to  the  improvement  of  the  parent 
stock,  from  which  such  marked  results  have  since  been  attained. 

I  do  not  now  remember  the  amount  of  cash  received  from  the  product 
of  this  half  acre.  I  shipped  the  melons  mostly  to  Mr.  Woodruff,  a  com¬ 
mission  merchant  of  Leadville,  who  sold  them  for  10  cents  per  pound,  which 
would  be  equal  to  about  $6.50  per  crate. 

As  the  patch  yielded  well  and  the  melons  sold  so  readily,  I  wished 
before  the  season  closed  that  I  had  planted  several  half  acres,  but  dur¬ 
ing  the  seven  years  in  which  I  grew  cantaloupes  at  Rockyford,  I  rarely 
exceeded  five  acres  each  year.  After  the  first  two  or  three  years  a  num¬ 
ber  of  other  farmers  began  growing  cantaloupes. 

In  those  early  years  the  market  was  not  crowded  and  by  culling  closely 
a  good  sale  was  realized  for  what  was  shipped.  The  cantaloupes  were 
gathered  in  sacks  and  packed  and  shipped  in  barrels  and  boxes,  and  as 
the  market  was  then  principally  in  Colorado  towns,  the  “empties”  were  re¬ 
turned  to  the  growers.  We  had  not  thought  of  shipping  in  car  lots,  although 
watermelons  were  already  being  shipped  in  that  way;  sometimes  straw 
was  placed  on  top  of  the  water  melons  and  cantaloupes  were  added  to  the 
car. 

We  had  no  thought  of  co-operative  organization  as  yet,  but  each  sue- 


4 


Bulletin  108. 


ceeding  year,  new  growers  were  added,  and  as  the  markets  began  to  be 
more  fully  supplied  with  cantaloupes,  they  were  sometimes  over  crowded 
at  the  height  of  the  season;  one  year  while  I  was  there,  the  growers  met 
and  apportioned  the  markets,  each  grower  agreeing  to  ship  only  to  his 
own,  during  the  rush  of  the  season,  thus  equalizing  the  supply  to  the 
various  markets. 

At  the  commencement  of  the  cantaloupe  industry,  a  com¬ 
paratively  small  area  was  under  cultivation.  Such  farms  as  were 
found  along  the  Arkansas  were  principally  stock  ranches,  pro¬ 
ducing  hay,  grain  and  alfalfa  seed.  The  gross  returns  from  any 
of  these  crops  were  comparatively  small,  and  the  valuation  of 
land  was  consequently  low.  In  the  vicinity  of  Rockyford,  even 
as  late  as  1897,  choice  lands  under  ditches  with  the  best  water 
rights  were  purchased  for  fifty  dollars  per  acre.  Hon.  G.  W. 
Swink  and  other  early  settlers  who  were  interested  in  the  de¬ 
velopment  of  the  valley,  were  enterprising  in  their  efforts.  In 
1889  Mr.  Swink  attended  a  Beet  Sugar  Convention  held  at  Grand 
Island,  Neb.,  with  a  view  of  interesting  the  Oxnard’s  in  the  Ar¬ 
kansas  Valley  as  a  suitable  location  for  a  Beet  Sugar  factory. 
He  became  convinced  that  the  farms  in  the  Arkansas  Valley  were 
too  large  and  the  population  too  small  to  offer  any  inducement 
to  the  sugar  beet  industry  at  that  time.  He  had  the  hope,  how¬ 
ever,  that  the  cantaloupe  industry,  which  had  already  brought  en¬ 
couraging  returns,  would  provide  a  larger  population  and  smaller 
farms,  and  thus  bring  about  the  conditions  necessary  for  the  beet 
industry.  Accordingly  on  his  return  to  Rockyford  he  set  to  work 
to  encourage  every  available  settler.  His  lands  near  Rockyford 
were  divided  into  five  and  ten  acre  tracts;  and  opportunities  to 
secure  homes  were  freely  offered  to  health  seekers  without  means, 
good  intention  being  the  principle  requirement.  The  lucrative 
promise  of  the  cantaloupe  industry,  as  well  as  the  light  character 
of  the  work,  appealed  to  an  intelligent  class  of  people  who  found 
the  climatic  conditions  of  the  East  too  severe. 

The  public  spirit  which  was  early  manifested,  as  well  as  the 
enterprising  character  of  the  community,  were  potent  factors  in 
the  development  of  the  cantaloupe  industry  and  led  to  the  in¬ 
tensive  farming  which  has  since  characterized  the  vicinity  of  Rocky¬ 
ford. 

During  ten  or  twelve  years,  small  farms  devoted  to  canta¬ 
loupe  culture  were  constantly  increasing.  Some  growers,  for¬ 
tunate  in  getting  early  melons  and  in  shipping  to  reliable  com¬ 
mission  merchants,  received  gratifying  returns ;  others  from  various 
causes  received  but  poor  returns  and  bewailed  their  fate  in  ever 
coming  to  the  valley. 

During  the  latter  part  of  the  first  decade,  it  became  evident 
that  the  production  of  cantaloupes  had.  reached  the  limit  of  the 


Development  oe  Rockyeord  CanataLoupe  Industry.  5 

market  then  developed.  One  of  the  first  evidences  of  “too  many” 
cantaloupes,  was  the  lack  of  boxes  and  barrels  for  shipping.  Ne¬ 
cessity,  however,  became  the  mother  of  invention,  and  someone 
conceived  the  idea  of  making  a  crude  crate.  Twelve-inch  board 
and  common  lath  were  utilized,  half  of  the  length  of  the  lath  be¬ 
ing  used  for  slats,  and  as  this  happened  to  accomodate  about  45 
averaged  sized  melons,  the  size  of  the  future  standard  crate  was 
thus  arbitrarily  determined.  Although  the  empty  boxes  were  con¬ 
stantly  being  returned  from  the  Pueblo  and  Denver  markets,  the 
local  supply  of  lath  and  twelve-inch  boards  was  soon  exhausted. 

Glowing  reports  from  the  first  shipments  of  the  season  cre¬ 
ated  .such  enthusiasm,  that  every  melon  which  could  possibly  be 
shipped  was  hurried  onto  the  market,  only  to  find  at  the  end  of 
the  season,  that  much  of  the  crop  had  not  paid  express  charges. 
The  high  prices  which  a  favored  few  obtained  at  the  beginning 
of  the  season  acted  like  a  lucky  strike  in  a  mining  camp,  and  each 
spring  found  new  growers  and  a  constantly  increasing  acreage. 

For  many  years  the  cantaloupes  were  shipped  entirely  by  local 
express,  each  grower  making  his  individual  consignments  to  the  var¬ 
ious  Colorado  markets.  In  1894  the  first  step  toward  co-opera¬ 
tive  effort  in  marketing  cantaloupes  was  taken,  groups  of  neigh¬ 
bors  combining  to  load  a  ventilator  car  and  ship  by  freight,  thus 
securing  greatly  reduced  transportation.  The  cars  were  con¬ 
signed  to  commission  men  on  the  various  markets  who  remitted 
to  the  individual  consignors  who  made  up  the  car.  Messrs.  G. 
W.  Swink,  A.  C.  Comer,  A.  P.  Kouns  were  representative  men 
in  these  early  shipping  groups.  Two  years  later  the  growers, 
for  the  first  time,  were  supplied  with  regular  crates  manufac¬ 
tured  at  the  lumber  mills.  These  were  of  the  same  dimensions 
as  the  first  crude  crate,  and  were  essentially  the  same  as  those 
that  have  since  been  used. 

Following  the  introduction  of  the  crate,  came  the  next  step 
towards  co-operative  organization,  when  one  of  the  shipping  groups, 
already  referred  to,  added  a  few  members,  elected  officers,  and 
effected  a  formal  organization  which  has  since  been  known  as  the 
“Kouns  Party.”  Their  plan  was  to  ship  to  specially  authorized 
agents  or  commission  men  who  contracted  to  handle  their  canta¬ 
loupes  exclusively.  They  shipped  most  of  their  cantaloupes  to 
Denver,  receiving  fair  returns  considering  the  glutted  condition  of 
the  Colorado  markets  that  season.  Their  organization  had  its  ad¬ 
vantages,  but  as  they  had  no  control  over  the  heavy  shipments 
of  others,  the  general  results  of  1896  were  a  repetition  of  former 
failures.  Many  growers  after  laboring  all  summer  to  produce  a 
crop  of  cantaloupes,  were  presented  with  bills  for  transportation, 
their  summer’s  labor  having  been  sacrified  as  they  believed,  to  the 


6 


Bulletin  108. 


railroad  and  commission  men.  A  few  cars  of  cantaloupes  which 
Messrs.  G.  W.  Swink  and  A.  C.  Comer  that  season  shipped  to 
Kansas  City  and  St.  Louis  caused  a  new  star  of  hope  to  rise  in 
the  Eastern  horizon,  and  visions  of  great  possibilities  for  future 
market  developments. 

The  unremunerative  returns  of  several  years  having  created 
a  strong  public  sentiment  that  something  must  be  done,  the  time 
seemed  to  be  ripe  for  a  more  comprehensive  co-operative  organiza¬ 
tion.  Accordingly  a  meeting  was  called  in  the  fall  of  1896;  by¬ 
laws  were  drafted  and  articles  of  incorporation  were  filed  for  the 
Rockyford  Melon  Growers  Association.  It  embraced  practically 
all  the  cantaloupe  growers  of  Otero  county  with  the  exception  of 
several  individuals  who  by  reason  of  the  organization  were  able 
to  secure  good  prices  from  certain  commission  men  who  were 
trying  hard  to  disrupt  the  organization.  The  Kouns  Party  was 
absorbed  by  the  Association,  it  being  understood  that  H.  Woods 
should  represent  the  Association  in  the  Denver  market.  The  gen¬ 
eral  plan  of  the  Association  was  to  market  all  cantaloupes  possible, 
and  when  from  lack  of  cars  or  insufficient  market,  the  melons  could 
not  be  handled,  the  grower  was  given  a  receipt  and  his  canta¬ 
loupes  returned  to  him  to  be  cut  for  seed  or  to  be  fed  to  stock. 
The  proceeds  of  those  which  were  marketed  were  divided  pro  rata 
according  to  the  receipts  which  the  growers  held. 

The  first  season  a  contract  was  made  with  the  Western  Poul¬ 
try  and  Game  Co.  of  St.  Louis,  Mo.,  which  agreed  to  take  thirty- 
five  cars  during  the  season  of  1897  at  75  cents  per  crate,  f.  o.  b.  at 
Rockyford.  The  quality  of  the  cantaloupes  that  season  was  ex¬ 
ceptionally  fine,  and  they  sold  so  readily  on  the  Eastern  markets, 
that  by  the  close  of  the  season  the  St.  Louis  firm  had  handled 
1 21  cars.  On  several  occasions,  circumstances  necessitated  the 
return  of  the  cantaloupes  to  the  grower,  which,  according  to  the 
terms  of  the  Association  were  receipted  for,  and  which  reduced 
the  average  price  per  crate  during  the-  season,  yet  for  once  in 
the  history  of  the  cantaloupe  industry,  the  returns  were  satisfactory. 

The  following  year  the  Manager  of  the  Western  Poultry 
and  Game  Co.  came  before  the  Association  and  reported  that 
tEe  previous  year  had  been  a  profitable  one  to  his  com¬ 
pany,  they  having  cleared  a  considerable  sum,  exclusive  of  large 
amounts  spent  in  advertising;  he  claimed  that  they  had  secured 
reliable  agents  in  New  York,  Pittsburg  and  other  cities  in  the 
East,  to  assist  them,  and  offered  to  contract  the  crop  of  1898  at 
97/4  cents  per  crate,  f.  o.  b.  at  Rockyford.  The  proposition  was 
received  with  enthusiasm. 

The  membership  of  the  Association  swelled  to  over  800  mem¬ 
bers,  and  the  acreage  increased  to  more  than  5,000  acres  in  Otero 


Development  op  Rockyeord  Cantaloupe  Industry.  7 

County.  With  the  exception  of  a  small  body  of  men  in  Prowers 
County  and  two  or  three  men  in  Otero  County  it  comprised  all 
the  cantaloupe  growers  in  the  Arkansas  Valley.  Never  before  was 
there  a  closer  organization  of  growers,  or  one  in  which  members 
were  more  persistent  in  their  determination  to  remain  loyal  to 
the  organization. 

Some  attempts  were  made  to  influence  growers  to  break  the 
contract  and  leave  the  organization,  some  men  even  having  their 
agents  meet  the  growers  on  the  road  to  the  station,  and  offer  an 
advance  over  what  they  expected  to  receive  through  the  Associa¬ 
tion,  but  as  there  was  a  general  feeling  that  they  had  been  vic¬ 
timized  by  such  men  there  is  no  record  of  any  grower  betraying 
the  Association. 

The  harvest  began  early  in  August,  a  few  crates  at  first  which 
rapidly  increased  until  14  cars  were  loaded  in  a  day.  This  jumped 
suddenly  to  28  cars  a  day  during  the  last  week  in  August.  Soon 
150  cars  were  rolling  to  the  Eastern  markets  when  it  was  realized 
that  the  market  would  be  glutted  before  the  week’s  heavy  ship¬ 
ment  could  arrive.  Telegrams  flashed  the  information  and  a  halt 
was  called,  while  the  commission  men  hurried  West  to  explain 
the  situation.  A  largely  attended  mass  meeting  of  growers  met 
at  the  Fair  Grounds  in  Rockyford  to  hear  the  report  of  market 
conditions.  By  telegrams,  letters  and  able  addresses,  they  were 
convinced  that  their  cantaloupes  were  not  so  marketable  as  in  the 
previous  year.  Over  one  hundred  cars  had  been  dumped  in  New 
York  City  alone  and  transportation  charges  of  many  thousands 
of  dollars  remained  unpaid,  which  it  was  claimed  they  were  re¬ 
sponsible  for  because  the  melons  were  not  merchantable. 

The  A.  T.  &  S.  F.  R.  R.  offered  to  cancel  the  transporta¬ 
tion  due  them  from  the  lost  cantaloupes.  The  commission  firm 
offered  to  pay  $18,000  of  the  $48,000  then  due  the  Association,  pro¬ 
viding  the  latter  would  waive  the  balance  and  accept  75  cents  per 
crate  for  the  balance  of  the  season.  This  proposition  was  accepted  by 
the  growers  though  it  afterwards  proved  that  the  firm  was  un¬ 
able  to  meet  their  promises  and  representatives  of  the  Association 
were  sent  East  to  investigate  the  disaster.  They  reported  and 
experience  has  since  shown  that  poor  refrigeration  was  the  chief 
cause  of  the  loss  of  the  cantaloupes,  the  truth  of  the  matter  being 
that  the  industry  had  out  grown  the  then  poorly  developed  mar¬ 
ket  facilities.  Experience  in  handling  the  crop  had  not  kept  pace 
with  the  increased  production. 

As  a  whole  the  season’s  results  were  highly  unsatisfactory. 
Seemingly  the  Association  idea  had  received  a  death  blow,  yet 
the  co-operation  idea  of  the  Association  was  not  abandoned,  it 
simply  changed  form.  The  various  shipping  points  of  La  Junta, 


8 


Bulletin  108. 


Fowler  and  Manzanola  withdrew  and  organized  Associations  of 
their  own,  then  a  Federation  was  perfected  including  these  sev¬ 
eral  Associations  which  provided  a  general  marketing  committee 
with  representatives  from  each  Association  who  were  empowered 
to  make  the  contracts  with  the  commission  men,  thus  uniform  con¬ 
tracts  were  secured  for  the  Valley. 

By  this  time,  the  cantaloupe  industry  had  been  the  cause  of 
a  large  increase  in  population  and  the  large  farms  had  been  broken 
up  into  smaller  tracts.  Then,  too,  in  1899  a  large  number  of 
field  tests  of  sugar  beets  by  farmers  demonstrated  the  possibilities 
in  the  Valley,  and  the  following  year  saw  the  construction  of  a 
factory  at  Rockyford,  thus  realizing  the  early  hopes  of  the  origi¬ 
nal  promoters  of  the  Valley. 

Many  growers  turned  their  attention  to  the  new  crop  so  that 
the  tension  of  the  cantaloupe  situation  was  somewhat  relieved,  and 
cantaloupe  growing  has  since  become  more  profitable,  the  average 
price  realized  having  gradually  increased.  It  is  true  there  have 
been  seasons  of  high  and  low  prices,  influenced  by  various  condi¬ 
tions  which  effect  the  marketing  of  any  crop,  such  as  over-produc¬ 
tion,  quality,  the  abundance  of  substitute  fruit,  etc. 

At  Rockyford  the  original  Association,  with  amended  by¬ 
laws,  was  continued  and  is  still  a  well  organized  body  of  growers. 
The  growers  who  had  been  previously  identified  as  the  “Kouns 
Party,”  withdrew  with  others  and  reorganized,  forming  the  “Kouns 
Party”  of  today.  Their  plan  has  been  to  ship  exclusively  on  com¬ 
mission,  each  car  being  treated  as  an  entirety  and  the  returns  pro¬ 
rated  among  the  growers  who  shipped  in  the  car.  The  plan  has 
been  popular  with  many  growers  and  a  number  of  Associations  in 
the  Valley  have  adopted  it,  shipping  through  the  same  commis¬ 
sion  firm — H.  Woods  of  Chicago. 

The  Rockyford  Association  and  those  federated  with  it,  since 
the  disaster  of  1898  have  also  resorted  to  the  commission  basis  in 
general,  shipping  through  the  joint  firms  of  Lyons  and  Coggins, 
the  main  difference  being  that  in  the  Rockyford  Association,  the 
returns  have  been  prorated,  at  first  in  daily  pools  and  later  in  the 
season  in  weekly  pools,  instead  of  by  the  car  as  in  the  Kouns  Party. 
The  latter  method  although  affording  a  quick  account  of  sales,  make 
the  returns  for  each  grower  more  subject  to  chance,  since  the 
particular  car  in  which  he  ships  may  or  may  not  encounter  favor¬ 
able  conditions.  Thus  in  this  plan  there  may  be  a  variation  in 
the  returns  which  different  growers  may  receive  who  have  shipped 
the  same  day  but  in  different  cars. 

It  might  be  well  to  state  that  up  to  the  present  time,  there 
has  been  no  classification  as  to  quality  there  being  but  one  grade 
of  inspection.  In  the  other  plan,  the  returns  for  the  day  or  week 


Development  oe  Rockyeord  Cantaloupe  Industry.  9 

being  pooled,  growers  shipping  at  the  same  period  will  receive 
the  same  returns  regardless  of  the  conditions  which  their  indi¬ 
vidual  melons  may  encounter.  Each  plan  has  its  advocates  and 
on  the  whole  both  have  given  satisfactory  results. 

Since  the  division  of  the  big  Association  of  1898,  most  of  the 
cantaloupes  have  been  marketed  through  the  organizations  and 
commission  men  above  mentioned,  yet  from  time  to  time,  other 
commission  men  have  made  efforts  to  gain  a  foot-hold  with  the 
growers.  Taking  advantage  of  low  market  conditions,  they  would 
report  high  returns  and  in  this  way  a  number  of  growers  have 
been  drawn  from  the  Associations.  One  after  another  of  these 
firms  has  come  and  gone,  each  time  leaving  a  sadder  but  more 
experienced  set  of  growers. 

The  presence  of  these  contending  elements  has  in  many  cases 
hampered  the  results  of  the  associations,  causing  unstable  condi¬ 
tions.  Thus,  when  the  management  insisted  on  the  rules  of  the 
Association  and  the  rigid  inspection  of  cantaloupes  necessary  to 
the  welfare  of  the  industry,  some  over  sensitive  grower  would 
“pull  out”  to  the  opposition  who  were  ready  and  willing  to  re¬ 
ceive  his  cantaloupes  regardless  of  condition.  A  number  of  in¬ 
stances  have  occurred  when  loads  of  green  or  otherwise  unmar¬ 
ketable  cantaloupes  have  been  refused  at  the  Association  plat¬ 
form,  only  to  be  immediately  driven  over  to  the  car  of  some  con¬ 
tending  commission  firm,  where  a  large  sum  would  be  paid  for 
the  first  load  with  promise  of  still  greater  returns  subsequently  if 
sent  on  commission.  The  result  of  trusting  these  promises,  has 
shown  them  to  be  but  a  bait.  Again  the  constant  canvassing  by 
these  commission  agents  has  tended  to  increase  the  acreage  of 
cantaloupes,  although  experience  has  shown  the  industry  to  be 
overdone  nearly  every  year. 

Not  only  this,  but  the  strife  and  competition  have  led  to  the 
shipping  of  green  unmarketable  melons  in  order  to  get  the  ad¬ 
vertising  which  comes  from  shipping  the  first  basket  or  crate  of 
Rockyfords.  Thus,  in  1894,  one  of  the  new  commission  firms  paid 
$10  for  a  crate  of  green  cantaloupes  which  were  shipped  a  week 
before  the  first  really  ripe  cantaloupes  were  ready  to  market. 

This  shipping  of  green  stock  stimulated  the  practice  in  all 
of  the  Associations  among  impatient  or  inexperienced  growers  and 
resulted  injuriously  to  the  reputation  of  the  Rocky  ford  cantaloupes 
and  has  been  an  outrage  upon  the  people  who  bought  the  fruit.  A 
cantaloupe  which  is  not  at  a  certain  stage  of  ripeness  when  picked 
will  never  be  fit  to  eat,  but  the  inexperienced  commission  man  rea¬ 
sons  that  because  fruit  such  as  lemons,  bananas  and  tomatoes  can 
be  marketed  quite  green  and  still  attain  perfection,  that  the  same 
can  be  done  with  cantaloupes.  This  is  a  fatal  mistake — as  well 


10 


Bulletin  108. 


try  to  market  green  peaches,  strawberries  or  watermelons,  which 
only  shrivel  down  and  are  worthless. 

Many  lessons  beside  those  mentioned  have  been  learned  in 
the  last  six  or  eight  years,  and  they  nearly  all  attest  the  merits  of 
well  organized  co-operative  efforts  to  secure  results. 

During  the  coming  season  of  1906,  the  organized  Associa¬ 
tions  will  doubtless  market  most  of  the  cantaloupes  from  the  Rocky- 
ford  district,  although  the  firm  of  Young  &  Mathis  of  New  York, 
who  are  large  growers  themselves,  and  who  ship  for  individuals 
to  some  extent,  may  be  a  possible  exception. 

The  growers  in  general  have  realized  to  their  sorrow  that 
the  old  adage,  “Competition  is  the  life  of  trade,”  is  a  poor  maxim 
when  applied  to  the  sale  of  cantaloupes  on  commission — the  com¬ 
mission  men  fight  and  the  growers  pay  the  bill.  This  has  become 
such  a  reality  that  it  has  produced  a  strong  sentiment  in  the  minds 
of  many  growers  in  favor  of  a  cash  proposition. 

As  a  result  in  recent  years  a  cash  advance  of  varying  amounts 
has  been  granted  in  many  of  the  contracts  with  the  commission 
men,  but  there  are  many  conditions  which  can  not  be  controlled, 
such  as  the  acreage  needed  to  supply  the  market  demands;  the 
preventing  of  outside  growers  from  selling  on  commission  and 
thus  competing  with  the  man  who  pays  cash,  all  of  which  seem 
to  preclude  the  possibility  of  getting  a  cash  price  which  would  equal 
that  now  realized  through  reliable  commission. 

If  the  element  of  competition  on  the  market  were  eliminated 
by  the  complete  co-operation  of  the  growers,  and  if  the  acreage 
were  not  increased  beyond  that  indicated  by  experience,  the  price 
of  cantaloupes  would  doubtless  become  more  uniform  from  year 
to  year. 

The  added  strength  of  the  established  Associations,  caused 
by  the  return  of  many  of  the  disaffected  growers;  the  securing 
of  a  uniform  strain  of  seed  for  the  members  of  these  Associations, 
and  the  improving  of  market  facilities  are  all  factors  which  seem 
to  promise  better  days  for  the  cantaloupe  industry  and  the  realiza¬ 
tion  of  the  co-operative  ideal  where  all  the  interests  of  the  canta¬ 
loupe  growers  become  mutual. 

Having  summarized  the  growth  of  the  industry  from  the 
grower’s  standpoint,  the  history  would  seem  to  be  incomplete  with¬ 
out  a  review  of  the  market  developments  as  witnessed  from  the 
distributing  man’s  point  of  view ;  for  in  order  to  make  possible  this 
great  industry  which  returns  to  the  grower  several  hundred  thou¬ 
sands  of  dollars  each  year,  joint  efforts  were  required  on  the  part 
of  both  growers  and  market  men,  and  without  this  co-operative 
effort,  the  industry  would  still  be  in  a  chaotic  condition. 

Lyons  Brothers  Co.  of  New  York  and  M.  O.  Coggins  Co. 


Development  op  Rockyford  Cantaloupe  Industry. 


ii 


of  Pittsburg  which  jointly  have  directly  or  indirectly  handled  the 
cantaloupes  of  the  Rockyford  Melon  Growers’  Association  since 
the  first  car  went  to  Eastern  markets,  and  H.  Woods  of  Chicago, 
who  has  marketed  the  cantaloupes  of  the  Kouns  Party  since  its 
organization,  represent  the  principal  distributing  agents  of  canta¬ 
loupe  growers’  organizations  in  Colorado  during  the  past  ten  years. 

Each  has  kindly  contributed  an  article  embodying  much  use¬ 
ful  information  relative  to  the  co-operative  organizations  and  the 
marketing  of  cantaloupes. 

Mr.  M.  O.  Coggins  of  Pittsburg  had  prepared  an  article  en¬ 
titled,  “The  Cantaloupe — From  a  Luxury  to  a  Necessity,”  which 
he  read  before  the  National  League  of  Commission  Merchants  in 
Milwaukee,  and  this  article  with  supplementary  information  was 
to  have  been  contributed  to  this  Bulletin,  but  before  he  had  time 
to  prepare  it,  his  sudden  death  immediately  following  his  return, 
occurred,  and  the  information  expected  to  have  been  obtained  from 
him,  is  limited  to  the  article  referred  to. 

His  unexpected  death  has  caused  a  severe  blow  to  the  canta¬ 
loupe  industry,  for  without  doubt  his  influence,  as  much  as  that 
of  any  one  man  has  made  possible  the  present  development  of  the 
industry.  Being  identified  with  it  from  the  first,  his  experience 
and  judgment  are  a  loss  which  will  be  felt.  It  was  through  his 
personal  influence  that  the  first  cars  were  shipped  east  of  St.  Louis. 
In  1897,  after  several  interviews  over  the  long  distance  telephone 
with  Mr.  Nat  Wetzel  of  St.  Louis,  he  induced  him,  by  a  guar¬ 
antee  of  $2  per  crate,  to  forward  a  car  of  Rockyford  cantaloupes, 
although  it  was  doubtful  whether  cantaloupes  could  be  carried  far¬ 
ther  east  than  St.  Louis.  Mr.  Coggins  lost  20  cents  per  crate  but 
made  good  his  guarantee,  and  the  merits  of  the  melons  becoming 
known,  he  was  able  to  realize  a  profit  on  subsequent  shipments, 
and  that  season  handled  8  cars  of  the  first  30  received  in  St.  Louis 
by  the  Western  Poultry  and  Game  Co. 

THE  CANTALOUPE,  FROM  A  LUXURY  TO  A  NECESSITY 

M.  O.  COGGINS. 

In  the  year  1870,  it  was  an  unusual  thing  to  see  a  muskmelon  on 
the  market,  but  long  in  the  eighties,  they  began  planting  in  the  Maryland 
Peninsula  a  variety  known  as  the  Anna  Rundels  and  also  some  Jenny 
Linds. 

These  were  placed  on  the  market  about  the  10th  of  July,  but  ship¬ 
ments  amounted  to  very  little  until  about  the  20th  of  July,  continuing  un¬ 
til  the  middle  of  August;  these  shipments  gradually  increased  in  quantity 
each  year  until  the  nineties,  although  the  total  receipts  on  the  New  York 
market  would  not  amount  to  three  cars  a  day  at  the  height  of  the  sea¬ 
son  and  the  prices  ranged  from  $2.50  to  $6.50  per  basket. 

Only  a  few  of  the  fruit  and  vegetable  men  handled  muskmelons  and 
they  supplied  the  hotels  and  restaurants.  The  high  prices  and  limited 
supply  made  the  cantaloupe  a  great  luxury,  too  expensive  for  the  average 
grocer  to  handle. 


12 


Bulletin  108. 


Beginning  with,  the  early  nineties,  there  was  a  gradual  increase  in 
quantity  as  other  sections  of  the  country  began  shipping  so  that  the  sea¬ 
son  gradually  began  earlier  until  melons  for  the  4th  of  July  market  were 
no  longer  considered  a  novelty. 

After  the  year  18  97,  when  Rockyfords  were  placed  on  the  different 
markets  and  the  standard  crate  established,  the  Rockyford  seed  for 
planting  came  to  be  in  great  demand  in  the  southern  states. 

In  1898,  the  first  cars  of  southern  cantaloupes  grown  from  Roc.ky- 
ford  seed  were  shipped  from  Hitchcock,  Texas,  and  in  the  following  yeai 
the  first  carloads  from  Florida  arrived  in  New  York  on  June  2;  these  were 
followed  by  shipments  from  Georgia,  the  Carolinas  and  other  points  far¬ 
ther  north,  keeping  a  steady  supply  on  the  market  until  the  last  ship¬ 
ments  of  the  Colorado  melons. 

The  effect  of  the  use  of  the  Rockyford  seed  and  of  the  standard 
crate  was  to  make  the  cantaloupe  a  standard  article  of  trade  so  that 
regular  quotations  could  be  made. 

Orders  were  received  from  cities  and  towns  tributary  to  the  large  re¬ 
ceiving  points,  causing  a  demand  at  small  points  as  well  as  large  ones. 
This  demand  has  increased  so  enormously  since  1897,  that  I  thought  possibly 
a  few  figures  carefully  estimated  would  be  of  interest. 

In  1897  the  amount  consumed  througout  the  United  States  was  not 
over  400  carloads,  gradually  increasing  until  during  the  past  season  of 
1905,  6,920  carloads  were  used  throughout  the  United  States.  The  three 
largest  markets  the  past  year  handled  1,4  60;  715  and  660  cars  respectively. 
While  the  season  for  cantaloupes  has  changed  from  a  period  of  less  than 
two  months  to  six  months  of  carload  business. 

The  past  three  seasons  have  opened  up  about  May  12  with  shipments 
from  Florida,  car  lots  having  been  received  on  the  market  as  early  as 
May  22.  During  the  height  of  the  season,  New  York  alone  has  received 
as  high  as  35  cars  in  a  day. 

Prior  to  the  introduction  of  the  Rockyfords,  the  markets  had  no  uni¬ 
form  style  of  package,  shipments  being  received  in  baskets,  barrels,  straw¬ 
berry  crates  and  sometimes  in  dry  goods  boxes.  There  being  no  uni¬ 
formity,  quotations  were  impossible,  but  with  the  establishment  of  the 
standard  crate  containing  a  uniform  number  of  cantaloupes,  the  canta¬ 
loupe  became  a  standard  article  of  fruit  which  can  be  quoted  intelli¬ 
gently,  the  buyer  knowing  what  he  is  to  receive  in  size  and  number,  since 
the  Rockyford  seed  produces  the  same  size  and  shape  in  all  states  and  is 
the  only  shape  of  cantaloupes  that  the  buyers  will  buy.  This  has  made 
it  possible  for  both  individuals  and  companies  to  plant  a  very  large  acreage. 

To  give  some  idea  of  the  seed  industry,  there  was  saved  in  the  past 
season  in  the  Rockyford  district,  from  90,000  to  100,000  pounds  for  dis¬ 
tribution  in  the  different  melon  growing  sections  of  the  country. 

Before  the  advent  of  the  Rockyfords,  a  ten-acre  patch  was  con¬ 
sidered  a  large  venture  for  any  one  grower  and  it  is  now  well  known 
that  in  some  states  one  grower  may  sometimes  attempt  as  high  as  150 
acres. 

Prior  to  the  Rockyfords  no  muskmelons  worth  speaking  of  were  raised 
south  of  the  Maryland  Peninsula  in  the  East,  and  Indiana  and  Missouri 
in  the  West;  at  the  present  time  there  are  grown  in  the  state  of  Florida, 
about  4,000  acres;  in  Georgia,  about  4,000  acres;  in  North  and  South 
Carolina,  about  4,500  acres,  to  say  nothing  of  the  aggregate  of  small 
acreage  in  other  states;  the  total  for  the  United  States  during  the  past 
season  being  not  less  than  58,600  acres. 

The  supply  from  the  beginning  is  continuous,  the  season  in  one  state 
over-lapping  that  in  another  so  there  is  no  time  after  the  commence¬ 
ment  of  the  melon  season  when  the  markets  are  not  supplied.  Thus  the 
trade  has  an  opportunity  to  handle  and  the  consumer  an  opportunity  to 
purchase,  so  the  cantaloupe  at  the  breakfast  table  is  no  longer  con¬ 
sidered  a  luxury  but  a  necessity. 


Development  oe  Rockyford  Cantaeoupe  Industry. 


i3 


EARLY  MARKET  CONDITIONS  OF  CANTALOUPES  ON 

THE  NEW  YORK  MARKET. 

EYON  BROTHERS  COMPANY. 

Prior  to  1897,  the  eastern  markets  were  supplied  with  Anna  Rundels, 
Jennie  Linds  and  the  Hackensack  variety  of  muskmeolon;  these  came  to 
the  New  York  market  in  packages  of  every  description,  there  being  no 
uniformity  of  package  or  any  effort  to  establish  one. 

The  melons  were  irregular  in  size,  variety  and  quality;  the  flesh  was 
generally  thin,  the  seed  cavity  large,  the  flavor  irregular. 

The  bulk  of  the  receipts  for  the  New  York  market  came  from  Mary¬ 
land,  Delaware  and  New  Jersey.  Evidently  there  was  no  systematic  or¬ 
ganization  of  the  growers  as  the  shipments  were  spasmodic;  at  times  the 
market  was  glutted,  at  other  times  deficient,  and  the  irregular  conditions 
which  prevailed  made  it  impossible  to  give  a  standard  market  quotation. 

The  melons  were  sold  by  men  whose  principle  business  was  the  sell¬ 
ing  of  vegetables  and  the  prices  realized  were  according  to  their  ideas 
rather  than  from  any  regular  market  quotation,  which  today  gives  the 
grower  accurate  information  of  the  condition  of  the  market. 

HOW  ROCKYEORDS  CHANGED  CONDITIONS. 

In  August,  1897,  Rockyford  cantaloupes,  packed  uniformly  in  crates 
containing  45  cantaloupes,  were  received  on  the  New  York  market;  the 
thick  flesh,  small  seed  cavity  and  delicious  flavor,  made  a  sensational  repu¬ 
tation  for  the  Rockyford  cantaloupe  as  being  the  very  finest  ever  placed 
on  the  New  York  market.  These  melons  we  received  from  the  Rockyford 
Melon  Growers’  Association,  and  the  form  of  crate  which  originated  there, 
was  soon  adopted  as  the  standard  package  for  market  quotations,  and 
soon  came  into  use  throughout  the  melon  growing  sections  of  the  United 
States. 

The  ready  sale  of  the  Rockyfords,  the  organization  of  the  growers 
which  insured  the  uniform  crates,  and  the  fact  that  the  melons  were 
grown  under  irrigation  and  about  the  same  quality  could  be  produced 
every  year,  were  facts  which  convinced  us  that  the  Rockyford  would  be¬ 
come  as  standard  an  article  of  trade  as  a  barrel  of  apples. 

^Accordingly,  we  determined  to  make  cantaloupes  one  of  our  specialties, 
and  for  several  years  were  the  only  house  in  New  York  handling  the  product. 
By  thorough  advertising  the  Rockyford  cantaloupe  became  famous  in 
all  the  Eastern  states. 

The  introduction  of  the  Rockyford  cantaloupe  prolonged  the  market 
season  in  New  York  City  from  about  September  5  to  the  middle  of  October. 

Experiments  showing  that  the  Rockyford  seed  would  reproduce  its 
superior  qualities  when  grown  in  the  South  or  East,  led  to  extensive  plant¬ 
ing  in  the  Southern  states — 700  acres  being  planted  in  these  states  in 
18  99.  The  melons  from  these  states  came  on  early  in  May,  thus  open¬ 
ing  the  market  two  months  in  advance  of  previous  years.  In  1905,  the 
first  crate  was  received  from  Florida  on  May  12,  and  the  supply  con¬ 
tinued  from  the  various  states  in  succession  until  October  2  3,  making  a 
period  of  nearly  six  months. 

The  fact  that  the  cantaloupe  seed  produced  in  Colorado  under  irri¬ 
gation,  will  produce  earlier  melons  and  of  a  superior  quality,  than  the 
same  strain  when  grown  in  other  states,  has  been  verified  each  year,  and 
thousands  of  pounds  are  annually  sent  to  the  Southern  states  and  Cali¬ 
fornia  from  Colorado. 

Owing  to  the  development  of  this  phase  of  the  industry,  it  behooves 
the  Colorado  grower  to  use  the  utmost  care  in  the  selection  and  develop¬ 
ment  of  his  seed,  in  order  to  maintain  the  trade  of  the  United  States  which 
looks  to  him  to  supply  a  superior  grade  of  seed. 

Every  communitty  of  growers  should  organize  an  association  which 
would  make  rules  enforcing  the  planting  of  a  strain  of  cantaloupe  seed 


14 


Bulletin  108. 


known  to  have  the  best  line  of  selection.  They  should  insist  on  uniform 
grading  and  packing  and  permit  no  inferior  cantaloupes  to  be  marketed 
or  even  cut  for  seed. 

By  such  action  a  reputation  can  be  secured  and  maintained  which  will 
greatly  benefit  the  melon  industry.  On  the  other  hand,  carlessness  on  the 
part  of  a  few,  may  work  irreparable  injury  to  the  industry. 

We  wish  to  express  our  satisfaction  in  dealing  with  organized  growers. 
It  has  been  more  satisfactory  to  the  growers  themselves  as  well  as  the 
trade,  and  the  co-oprative  spirit  that  has  been  shown  in  some  of  the  com¬ 
munities  of  the  melon  growing  section  in  Colorado,  is  worthy  of  being 
emulated  in  other  sections  of  the  country. 

Transportation  under  modern  refrigeration  has  made  possible  the 
great  melon  industry.  Melons  will  carry  to  the  most  distant  markets  if 
the  proper  conditions  are  provided.  Usually  the  melons  are  warm  when 
loaded,  the  temperature  often  being  over  a  hundrd  degrees  in  the  shade. 

The  car  may  stand  six  or  eight  hours  before  it  is  made  up  and  even 
if  it  starts  soon  after  being  loaded,  the  enormous  heat  in  350-400  crates 
of  melons  is  more  than  the  ice  in  the  bunkers  can  absorb;  the  hot,  close 
air  generates  a  ferment  that  results  in  the  partial  or  complete  loss  of 
the  melons.  It  is  a  fact  that  in  cars  of  cantaloupes  which  heat  or  are 
spoiled,  the  injury  is  done  in  the  first  24  hours. 

Mr.  Li.  M.  Lyons,  the  President  of  our  Company,  has  been  studying  the 
problem  and  has  perfected  a  patent  cooling  process,  which  exhausts  the 
hot  air  while  the  car  is  being  loaded  and  waiting  to  start  on  its  long 
journey,  thus  avoiding  the  formation  of  degenerating  gases. 

During  the  season  of  1905,  the  process  was  used  for  the  first  time 
at  Thermal,  Cal.;  the  cars  were  three  days  in  being  loaded  and  the  out¬ 
side  temperature  during  the  day  varied  from  123-130  degrees  in  the  shade, 
but  arrived  in  New  York  in  perfect  condition  and  sold  as  high  as  $2,506 
gross,  per  car. 

During  the  coming  season,  the  process  will  be  tested  in  Colorado  and 
the  Southern  states. 

MARKET  DEVELOPMENT  OF  THE  ROCKYFORD  CAN¬ 
TALOUPE. 

H.  WOODS. 

My  experience  with  the  Rockyford  cantaloupe  began  in  Denver,  fifteen 
years  ago  when  one  wagon  could  have  delivered  the  daily  consignments 
and  my  yearly  sales  did  not  exceed  $500.  Since  that  time  I  have  witnessed 
the  growth  of  the  industry  and  its  market  developments  until  the  present 
time  when  my  cantaloupe  business  amounted  to  $250,000  for  the  season 
of  1905. 

A  story  of  the  early  market  conditions  of  the  Rockyford  cantaloupe 
would  be  a  varied  one,  telling  of  irregular  cantaloupes,  in  irregular  pack¬ 
ages,  coming  in  irregular  consignments  to  irregular  commission  men,  who 
remitted  irregular  returns  to  irregular  growers. 

From  the  beginning  of  my  experience  in  Denver,  the  market,  at 
some  period  in  nearly  every  season  would  be  over-crowded  with  melons. 

The  melon  is  at  best  a  very  perishable  article  and  may  be  in  per¬ 
fect  condition  today,  but  soft  and  undesirable  tomorrow.  When  the 
market  is  over-supplied  each  subsequent  consignment  makes  more  difficult 
the  sale  of  stock  already  on  hand,  consequently  the  price  drops,  and  trans¬ 
portation  charges  may  not  be  realized.  This  has  been  the  cause  of  many 
of  the  discouraging  remittances  to  growers. 

The  recollection  of  some  of  the  critical  experiences  of  the  early  melon 
market  in  Denver  is  far  from  pleasant.  Often  the  commission  houses 
were  overstocked  and  yet  in  spite  of  repeated  advices  by  mail  and  wire, 
the  growers  would  continue  their  consignments,  although  there  was  lit¬ 
tle  hope  of  even  securing  transportation  charges. 


Development  op  Rockypord  Cantaloupe  Industry. 


i5 


The  adoption  of  the  standard  crate  and  the  co-operative  idea  of  some 
of  the  growers,  made  possible  the  wider  development  of  the  cantaloupe 
market  throughout  the  United  States. 

The  subsequent  organization  of  the  growers  to  provide  a  satisfactory- 
market  for  their  cantaloupes  was  a  wise  step. 

The  season  of  1898  was  a  disastrous  one.  The  elements  leading  to 
this  failure  being,  poor  quality,  a  partial  failure  in  refrigeration,  over¬ 
production,  and  .  the  fact  that  a  large  proportion  of  the  men  handling 
the  cantaloupes  in  the  East,  had  but  little  experience  or  knowledge  of  the 
product,  and  the  proper  method  of  handling  on  the  market. 

Believing  my  experience  with  the  Rockyford  cantaloupe  in  Colorado 
would  be  useful  to  myself  and  the  industry,  and  the  industry  having  now 
become  national  rather  than  local,  in  1899,  I  contracted  to  handle  on 
a  commission  basis  the  cantaloupes  of  the  Kouns  Party  on  the  Eastern 
market. 

I  went  to  New  York  to  thoroughly  study  the  conditions  in  the  East, 
and  to  discover  what  improvements  could  be  made  in  the  distribution 
and  handling  of  the  cantaloupes  on  the  Eastern  market,  also  the  neces¬ 
sities  for  their  proper  transportation  and  refrigeration. 

From  my  experience  and  observation  that  year,  I  decided  that  Chi¬ 
cago  was  the  best  point  from  which  to  distribute  the  product. 

Chicago  was  not  only  one  of  the  largest  cities  in  the  country,  but 
it  was  on  the  only  line  of  railroad  running  through  the  cantaloupe  belt  of 
Colorado,  although  as  yet  Chicago  consumed  but  very  few  Rockyford 
cantaloupes. 

Accordingly  in  1900  I  located  in  Chicago  continuing  my  contract  with 
the  Kouns  Party  and  other  Associations  in  the  Rockyford  country. 

My  long  experience  in  the  business,  enabled  me  to  secure  good  re¬ 
sponsible  parties  in  all  the  leading  cities  of  the  country  to  handle  these 
cantaloupes  for  me.  In  the  Chicago  office,  I  was  in  daily  touch  by  wire 
with  all  these  agents,  also,  with  the  conditions  of  the  cars  in  transit.  These 
were  inspected  at  the  Missouri  River  and  again  at  Chicago  and  forwarded 
to  the  different  markets  according  to  their  condition,  only  the  firmest  and 
best  stock  being  allowed  to  continue  on  the  long  journey  to  the  seaboard. 

It  has  taken  'since  1899  to  build  up  this  system  and  secure  agents 
who  can  always  be  relied  on  to  give  attention  'to  the  business  at  the 
proper  time. 

The  average  price  paid  to  the  grower  gradually  increased  from  1899 
to  1903,  averaging  about  a  dollar  per  crate  for  the  period  of  five  years. 
The  increase  in  price  had  two  results  which  led  to  the  almost  complete 
failure  of  1904:  1st  the  profits  to  the  grower  during  the  period  of  pros¬ 
perity  led  to  more  extensive  planting,  resulting  in  over-production;  2d, 
the  profits  to  the  distributors  during  the  same  period,  led  new  men  with¬ 
out  a  comprehensive  knowledge  to  go  into  the  field  and  contract  as  dis¬ 
tributors;  this  increased  competition,  led  to  the  placing  of  many  inferior 
melons  which  otherwise  would  not  have  been  shipped,  thus  further  over¬ 
crowding  the  markets  and  lowering  the  price  below  the  point  of  profit¬ 
able  production,  and  in  the  case  of  some  firms  at  an  actual  loss  to  the 
grower. 

The  poor  results  of  1904  materially  decreased  the  acreage  for  1905 
and  caused  a  much  larger  proportion  of  the  melons  to  be  handled  by 
experienced  distributors,  so  that  the  results  to  the  grower  were  again 
satisfactory,  reaching  the  highest  average  paid  the  grower  in  the  his¬ 
tory  of  the  melon  industry  in  Colorado. 

To  sum  up  the  situation:  The  successful  distributor  must  thoroughly 
know  the  source  of  supply;  understand  the  handling  of  the  melons  from 
the  field  to  the  car,  also  the  loading  and  cooling  of  cars,  the  proper  re¬ 
frigeration,  the  conditions  and  requirements  of  the  different  markets, 
and  must  have  capable  and  experienced  agents  to  handle  the  melons  in 
the  different  cities  of  the  country. 

These,  together  with  the  support  of  an  organization  of  growers, 


i6 


Bulletin  108. 


who  are  loyal  to  their  own  best  interests  as  represented  by  the  objects 
of  their  association,  will  assure  the  prosperity  of  the  industry. 

TRANSPORTATION. 

During  the  last  nine  years,  5,999  cars  of  cantaloupes  were 
shipped  out  of  the  Rockyford  district,  being  an  average  of  666 
cars  per  annum.  In  1904  the  largest  number  were  shipped,  1,182 
cars,  and  in  1897  the  smallest  number,  121  cars. 

The  transportation  feature  of  the  cantaloupe  industry  is  perhaps 
the  most  important  of  any.  In  the  early  stages  of  the  cantaloupe 
industry  the  largest  cars  in  use  measured  from  32-34  feet  in  length, 
outside  measurement.  Today  the  predominating  car  is  40  feet, 
outside  measurement,  which  allows  32  feet  5  inches  inside  length; 
8  feet  2  inches  width  and  7  feet  3  inches  in  height. 

The  crates  are  loaded  lengthwise  and  space  allowed  between 
each  tier  for  the  circulation  of  the  cold  air.  A  40  foot  car  per¬ 
mits  24,000  pounds  or  366  standard  crates  of  66  pounds  each,  to 
be  loaded  in  tiers  not  exceeding  three  crates  in  height,  except  a 
few  tiers  near  the  ice  box.  The  warm  air  necessary  rises  to  the 
top  of  the  car,  and  if  the  cars  are  loaded  more  than  three  tiers  high, 
the  top  tier  generally  arrives  at  its  destination  in  a  worthless  con¬ 
dition. 

It  has  been  the  experience  of  all  receivers  during  the  past  years 
that  it  is  not  best  to  load  cars  to  exceed  24,00  pounds,  or  364  prates. 

The  system  of  icing  the  cars  in  vogue  at  present  is  to  ice  the 
empty  cars  at  La  Junta  during  the  night  and  send  them  on  .  a 
special  train  about  6  o’clock  in  the  morning  to  the  Rockyford  dis¬ 
trict  and  stations  west,  or  by  the  east-bound  freight  to  stations  in 
the  Las  Animas  district.  • 

The  initial  icing  requires  about  9,000  pounds.  After  load¬ 
ing,  the  cars  are  returned  to  La  Junta  and  re-iced  with  about.  6,000 
pounds  of  ice. 

The  melon  train  arrives  at  La  Junta  from  stations  in  the 
Rockyford  district  about  9  p.  m.  After  re-icing  the  cars  they 
depart  for  the  East  on  trains  leaving  La  Junta  about  midnight. 
In  the  height  of  the  season,  the  train  is  a  complete  melon  train. 

During  the  very  warm  weather  when  the  temperature  ranges 
to  90  degrees  and  upwards,  the  rear  vents  are  left  open  until  Dodge 
City  is  reached.  This  is  for  the  purpose  of  permitting  the  gases 
and  hot  air  to  escape  from  the  car.  Cars  re-iced  at  Dodge  City 
take  an  average  of  about  4,000  pounds  of  ice.  The  next  icing 
station  is  Newton,  Kan.,  where  about  5,000  pounds  more  of  ice 
are  required.  Argentine  follows,  with  4,500  pounds. 

The  run  from  La  Junta  to  Argentine  is  36  hours.  At  La 
Junta,  Newton  and  Argentine,  the  S.  F.  R.  D.  Co.  and  St.  F.  R.  R. 
each  have  ice  inspectors  whose  duty  is  to  see  that  the  cars  are 


Development  of  Rockyeord  Cantaloupe  Industry. 


17 

properly  iced  in  accordance  with  instructions.  These  require  that 
the  ice  shall  not  be  in  chunks  larger  than  50  pounds  and  that  the 
bunkers  shall  be  filled  to  full  capacity  at  each  icing  station.  There 
is  no  salt  used  but  the  ice  is  properly  packed  into  the  bunkers. 

Argentine  is  a  diversion  point  for  most  of  the  receivers  and 
each  has  a  representative  to  inspect  the  condition  of  the  canta¬ 
loupes  as  well  as  the  ice  in  the  bunkers.  On  the  report  of  the 
inspectors  at  Argentine  is  determined  the  diversion  to  long  or 
short-haul  points.  The  run  from  Argentine  to  Chicago  is  30  hours. 

Cars  are  re-iced  at  Corwith,  the  outer  yard  of  the  S.  F.  R.  R. 
at  Chicago,  and  usually  require  from  2,500-3,000  pounds  of  ice. 

Full  record  of  the  movement  of  all  cars  is  kept  by  the  S.  F. 
R.  R.  Co.,  being  received  by  wire  from  La  Junta,  Dodge  City, 
Newton  and  Argentine.  Diversions  may  be  accomplished  at  any 
point  from  the  line  of  the  S.  F.  R.  R.  on  very  short  notice,  by 
reason  of  this  accurate  record.  Some  through  cars  for  the  East¬ 
ern  markets  do  not  pass  through  Chicago  but  are  given  to  the  I.  I. 
&  I.  R.  R.  or  some  other  outer  belt  line  which  delivers  to  the  East¬ 
ern  connections  without  passing  through  Chicago,  but  on  account 
of  the  advantage  of  inspecting  cars  at  Corwith,  it  has  been  deemed 
advisible  in  late  years  to  have  all  cars  pass  through  Chicago.  The 
melon  train  usually  arrives  at  Corwith  between  5  and  6  p.  m.,  leav¬ 
ing  ample  time  to  re-ice  cars  and  make  Eastern  connections. 

The  Bohn  patent  refrigerator  car  is  used  by  the  S.  F.  R.  R. 
Co.  giving  more  satisfactory  refrigeration  than  the  old  style  for 
the  reason  that  the  ice  tanks  are  not  covered  but  separated  by  a 
grating  only,  thus  allowing  the  cold  to  permeate  the  car,  and  in 
this  manner  the  car  receives  the  full  advantage  of  the  ice. 

In  former  years,  cantaloupe  cars  were  not  iced  prior  to  load¬ 
ing  and  then  re-iced  immediately  after  loading.  The  custom  was 
to  ice  cars  at  La  Junta,  send  them  down  to  loading  stations  and 
not  re-ice  until  cars  reached  Argentine.  By  that  time  the  ice  in 
the  bunkers  was  practically  exhausted,  the  melons  ruined,  and  all 
the  ice  which  could  be  put  in  the  bnnkers  could  not  restore  the 
damage  to  the  melons.  The  striking  contrast  of  the  present  sys¬ 
tem  of  re-icing  the  cars  immediately  after  loading  and  keeping  the 
bunkers  well  filled  to  destination,  uniformly  brings  the  cars  to  des¬ 
tination  in  first  class  condition  and  claims  for  damages  are  reduced 
to  the  minimum. 

The  time  consumed  in  transporting  cars  from  Chicago  to  New 
York  is  about  60  hours,  and  from  Chicago  to  Boston  about  84 
hours.  When  cantaloupes  are  in  good  condition  when  picked  and 
are  loaded  properly,  the  cars  well  iced  and  transported  without 
unnecessary  delay,  they  should  arrive  even  on  the  Atlantic  sea¬ 
board,  in  practically  as  good  condition  as  when  shipped. 


Bulletin  109 


April,  1906 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College. 


Cultural  Methods  for  Sugar  Beets 


PROGRESS  BULLETIN 


By  W.  H.  OLIN 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
Fort  Collins,  Colorado. 

1906. 


The  Agricultural  Experiment  Station. 

FORT  COLLINS,  COLORADO 


The  state  Board  of  agriculture 


Hon.  P.  F.  SHARP,  President . 

Hon.  HARLAN  THOMAS . 

Hon.  JAMES  L.  CHATFIELD . 

Hon.  B.  IT.  DYE . 

Hon.  B.  F.  ROCKAFELLOW . 

Hon.  EUGENE  H.  GRUBB . 

Hon.  A.  A.  EDWARDS . 

Hon.  R.  W.  CORWIN . 

Governor  JESSE  F.  MCDONALD,  [ 

President  BARTON  O.  AYLESWORTH,  \ 


Denver . 

Denver . 

Gypsum  .... 
Rocky  Ford 
Canon  City. 
Carbondale . 
Fort  Collins 
Pueblo . 


ex-officio. 


TERM 

EXPIRES 

....1907 
..  .1907 
....1909 
. . . . 1909 
....1911 
....1911 
....1913 
....1913 


A.  M.  HAWLEY,  Secretary  EDGAR  AVERY  Treasurer 


Executive  Committee  in  Charge 

P.  F.  SHARP,  Chairman.  B.  F.  ROCKAFELLOW.  A  A.  EDWARDS 


STATION  STAFF 


L.  G.  CARPENTER,  M.  S.,  Director 

C.  P.  GILLETTE,  M.  S . 

W.  P.  HEADDEN,  A.  M.  Ph.  De... 

W.  PADDOCK,  M.  S . 

W.  L.  CARLYLE,  M.  S . 

G.  H.  GLOVER,  B  S.,  D.  V.  M . 

W.  H.  OLIN,  M.  S.,  . 

R.  E.  TRIMBLE,  B.  S . 

F.  C.  ALFORD,  M.  S . 

EARL  DOUGLASS,  M.  S . 

S.  ARTHUR  JOHNSON,  M.  S . 

B.  O.  LONGYEAR,  B.  S . 

J.  A.  McLEAN,  A.  B.,  B.  S.  A . 


. Irrigation  Engineer 

. Entomologist 

. Chemist 

. Horticulturist 

. Agriculturist 

. Veterinarian 

. . Agronomist 

Assistant  Irrigation  Engineer 

. Assistant  Chemist 

. Assistant  Chemist 

. Assistant  Entomologist 

.  Assistant  Horticulturist 

. Animal  Husbandman 


E.  B.  HOUSE . Assistant  Irrigation  Engineer 

F.  KNORR .  Assistant  Agriculturist 

P.  K.  BLINN,  B.  S . Field  Agent,  Arkansas  Valley,  Rocky  Ford 

O.  B.  WHIPPLE,  B.  A . Field  Horticulturist 

ESTES  P.  TAYLOR,  B.  S .  Field  Entomologist 


OFFICERS 


President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L  G.  CARPENTER,  M.  S . Director 

A.  M.  HAWLEY . Secretary 

MARGARET  MURRAY . Stenographer  and  Clerk 


CULTURAL  METHODS  FOR  SUGAR  BEETS 


PROGRESS  BULLETIN 


By  W.  H.  Olin 


I.  Sugar  Beet  Investigations  Already  Made  at  the 
Colorado  Experiment  Station.— Investigation  work  on  sugar 
beets  was  begun  by  the  Agricultural  College  before  the  organization 
of  the  Experiment  Station.  This  was  done  under  the  direction  of 
President  C.  E.  Ingersoll  who  had  great  belief  in  the  possibilities  of 
sugar  beets.  The  first  bulletin  on  sugar  beets  issued  by  the 
Experiment  Station  was  No.  7  in  1888.  Since  then  it  has  pub¬ 
lished  twelve  bulletins  on  the  subject  of  sugar  beets.  Most  of  these 
bulletins  were  prepared  by  the  Chemical  section  of  the  Station  and 
dealt  quite  largely  with  the  chemical  properties  of  beets  and  effect 
of  soil  conditions  upon  the  crop. 

Prof.  W.  W.  Cooke  (Professor  of  Agriculture)  in  1898  began 
a  study  of  cultural  methods,  seeking  to  determine  the  best  time  for 
planting,  best  distance  between  rows,  proper  distance  for  thinning 
in  the  row  and  how  to  handle  the  irrigating  water  to  obtain  the 
best  crop.  These  experiments  were  reported  in  bulletin  15  and 
were  strongly  in  favor  of  early  planting.  Definite  conclusions  were 
not  obtained  upon  the  other  problems,  which  still  await  solution. 

II.  Cultural  Methods  of  our  Most  Successful  Sugar 
Beet  Growers. — To  learn  the  cultural  methods  practiced  by  our 
most  successful  sugar  beet  growers,  question  circulars  were  sent  to 
1000  beet  growers  well  distributed  in  three  beet  regions  of  the  State; 
Northern  Colorado,  Arkansas  Valley  and  the  Western  Slope  region. 
These  growers  were  selected  as  representing  the  growers  who  were 
obtaining  the  best  tonnage  and  therefore  gettingthe  most  profitable 
crop  returns.  The  circulars  were  sent  out  in  June  and  October 
of  the  crop  season  1905.  They  contained  the  following  questions: 

1.  Number  of  acres  you  now  have  seeded  in  sugar  beets? 

2.  Number  of  acres  you  had  in  sugar  beets  last  year? 

3.  Date  of  seeding  beets  last  year? 

4.  Date  of  seeding  beets  this  year? 

5.  Amount  of  seed  used  per  acre? 

0.  Do  you  tend  your  own  beets? 


4 


THE  COLORADO  EXPERIMENT  STATION 


PLATE  i.  — desirable  types  of  sugar  beets 
(topped  beets  indicate  method  of  topping) 


CULTURAL  METHODS  FOR  SUGAR  BEETS 


5 


7.  If  you  employ  labor,  which  have  been  the  most  satisfac¬ 

tory— Italian,  Mexican  or  Russian  help? 

8.  Do  you  fall  plow  or  spring  plow  for  beets? 

9.  How  do  you  prepare  your  seed  bed  for  beets?  (Please  name 

the  operations.) 

10.  What  rotation  do  you  practic  for  beets — that  is,  what  crops 

do  you  grow  after  beets,  before  you  again  plant  the  same 
ground  to  beets? 

11.  How  many  times  do  you  cultivate  your  beets? 

12.  How  many  times  and  when  do  you  irrigate  your  beets? 

13.  Do  beets  require  more  or  less  water  than  other  crops? 

14.  How  many  loads  of  manure  per  acre  do  you  consider  best 

for  beets?  What  kind? 

15.  How  many  seasons  do  you  think  you  can  obtain  a  satisfac¬ 

tory  yield  of  beets  without  manure? 

16.  What  is  your  experience  with  barnyard  manure  for  beets? 

17.  Do  you  advise  the  use  of  commercial  fertilizer  for  beets? 

If  so,  what  kind? 

18.  What  is  the  character  of  your  soil? 

19.  What  do  you  consider  the  after  feed  (tops,  etc.)  left  on  the 

ground  worth? 

20.  What  tonnage  per  acre  did  you  harvest  last  year? 

21.  What  was  your  net  profit  per  acre  last  year?1 

22.  What  is  the  average  expense  per  acre  for  growing  beets  on 

your  land? 

23.  How  do  beets  compare  financially  with  other  crops? 

24.  Would  you  advise  your  neighbor  to  grow  sugar  beets  as  a 

profitable  crop? 

25.  What  trouble  have  you  had  with  insects  or  plant  diseases 

attacking  your  plants? 

26.  To  what  space  between  plants  do  you  prefer  to  thin  your 

beets?  Will  a  greater  distance  increase  or  decrease  the 
tonnage  and  size  of  beets? 

27.  Have  you  grown  a  satisfactory  beet  crop  on  alfalfa  sod? 

28.  Do  you  think  a  grain  or  other  crop  should  be  grown  on  al¬ 

falfa  sod  before  planting  to  beets? 

29.  What  is  the  effect  of  early  and  late  seeding  upon  the  yield 

and  quality  of  beets? 

30.  Does  late  summer  irrigation  tend  to  ripen  the  beets  earlier 

or  does  it  seem  to  prolong  the  period  of  ripening? 

31.  When  did  you  pull  your  beets  this  season? 

'  32.  What  was  your  1905  yield? 

33.  What  was  your  per  cent,  tare  at  factory? 

34.  Was  this  caused  by  shape  of  beet,  manner  in  which  the 

beets  were  harvested,  or  dirt  on  beets? 

35.  What  was  the  condition  of  the  ground  when  you  pulled 

your  beets? 

36.  Was  the  beet  crop  a  satisfactory  one.  in  your  neighborhood 

this  season?  What  was  the  average  tonnage  per  acre? 

37.  What  suggestions  in  reference  to  sugar  beet  culture  or  prob¬ 

lems  which  you  believe  essential  will  you  give  us? 


It  is  to  be  regretted  that  many  to  whom  this  circular  was  sent 
neglected  to  send  in  reports.  Less  than  50  per  cent,  sent  in  a  com¬ 
plete  report  from  which  we  can  quote.  From  the  replies  sent  in 
to  these  question  circulars,  the  following  facts  were  gleaned: 

1.  Plowing  of  Beet  Ground. — 54  per  cent,  of  those  report- 
ing,  plow  their  beet  ground  in  the  spring;  26  per  cent,  plow  their 


6 


THE  COLORADO  EXPERIMENT  STATION 


PLATE  II  .—undesirable  types  of. sugar  beets 


CULTURAL  METHODS  FOR  SUGAR  BEETS. 


7 


beet  ground  in  the  fall;  20  per  cent,  irregular,  part  of  the  time 
spring  plowing  and  occasionally  disked  potato  ground. 


TABLE  No.  1. 

PLOWING  BEET  GROUND  AND  RESULTING  YIELDS 

(IN  TONS  PER  ACRE). 


Sp  ring 

Fall. 

Indif¬ 

ferent 

Arkansas  Valiev . 

Western  Slope 

18  1 
18.0 

16  7 

19  2 

16  6 

14  5 

18.2 

16.0 

17.2 

Northern  Colorado 

Further  data  is  necessary  to  show  the  value  of  fall  plowing 
recommended  for  every  section  of  the  state  growing  sugar  beets. 

2.  Date  of  Seeding. — Between  first  week  in  April  and  first 
week  in  June;  61  per  cent,  seed  in  the  month  of  May. 


TABLE  No.  2. 

TIME  OF  SEEDING  AND  AVERAGE  YIELD  PER  ACRE 

(IN  TONS  PER  ACRE). 


Localitv. 

April. 

May. 

June. 

Arkansas  Valley . 

19.3 

20.6 

18.3 

Western  Slope  . . . 

17.6 

17.7 

Northern  Colorado 

15  7 

18.4 

*20.0 

*OnIy  one  reported  June  planting,  therefore  it  is  not  comparative. 


The  study  of  time  of  planting  shows  more  clearly  than  this 
table  reveals  that  usually  early  planting  is  best  for  yield  and  qual¬ 
ity. 

3.  Amount  of  Seed  per  Acre. — The  amount  of  seed  used 
was  from  12  to  25  lbs.  per  acre.  The  great  majority  reported  using 
15  to  20  lbs.  per  acre. 

TABLE  No.  3. 


AMOUNT  OF  SEED  PER  ACRE  AND  AVERAGE  YIELD 

(IN  tons  per  acre). 


12 

lbs. 

13 

lbs. 

14 

lbs. 

15 

lbs. 

16 

lbs. 

17 

lbs. 

.18 

lbs. 

19 

lbs. 

20 

lbs. 

21 

lbs 

22 

lbs. 

23 

lbs. 

24 

lbs. 

25 

lbs. 

Ark.  Valley . 

14 

19.8 

19.3 

18  5 

27.5 

Western  Slope 

*22 

19.6 

16  0 

17.0 

19.0 

18  0 

Northern  Colo. 

*20 

18 

15  5 

17.0 

17.1 

19.2 

14 

18.5 

Average  Yield.. 

21 

18 

16  3 

16.5 

17  9 

19  1 

14 

18  3 

*Only  one  reported  12  lbs.  seed  per  acre.  The  majority  reported  the  use  of  from  15 
to  20  J bs .  per  acre. 


8 


THE  COLORADO  EXPERIMENT  STATION 


4.  Help  Preferred.  — 46  per  cent,  of  those  reporting  pre¬ 
ferred  Russian  labor.  No  particular  class  of  laborers  received  a 
satisfactory  vote  from  the  rest. 

y.  Space  Thinned  in  Rows. — ' This  varied  from  6  to  16  inches 
the  average  being  10.4  inches. 

TABLE  No.  4. 

SPACES  THINNED  IN  ROWS  AND  AVERAGE  YIELDS. 


(IN  TONS  PER  ACRE)., 


8  to  10  in. 

11  to  18  in. 

14 

to  16  in. 

Arkansas  Valley .  . . 

Western  Slope  . --- 

Northern  Colorado . 

18. 

17.7 

15.7 

20. 

19.7 

18.4 

28. 

20. 

Average  . 

17.1 

19.8 

21.5 

The  majority  reported  from  10  to  12  inches.  Further  work  is 
necessary  on  this  point.  The  table  clearly  shows  the  advantage  in 
point  of  yield  for  the  wider  spaces  in  the  row. 

6.  Number  of  Cultivations. — 44  per  cent,  cultivate  4  to  5 
times.  31  per  cent,  cultivate  6  to  7  times.  25  per  cent,  stated 
they  cultivated  two,  three,  eight,  ten  or  as  many  times  as  the  crop 
seemed  to  require  cultivation. 


TABLE  No.  5. 

NUMBER  OF  TIMES  CULTIVATED  AND  AVERAGE  YIELDS. 

(in  tons  per  acre.) 


3 

4 

5 

6 

7 

8 

As  oft^n 
as  needed 

Arkansas  Valley  ... 

20.0 

16.6 

20. 

22.2 

17. 

18.5 

Western  Slope . 

19.2 

19. 

17. 

20.0 

Northern  Colorado 

39.6 

18.3 

16. 

18. 

*13.5 

17.0 

Average . 

19.3 

18.3 

17.2 

18.3 

17.8 

17. 

18.5 

*  Only  one  reported 


This  table  does  not  give  us  positive  data  and  further  work  is 
necessary  to  draw  conclusions. 

7.  Times  Irrigated. — 56  per  cent,  report  two  to  three  times. 

18  per  cent,  report  four  times. 

15  per  cent,  report  often  as  needed. 

From  answers  sent  no  definite  data  on  yields  could  be  obtained. 


CULTURAL  METHODS  FOR  SUGAR  BEETS 


9 


1  _  •  COLO  Af«  EXPT,  STA 

PLATE  1 1 1  .  —  VARYING  TYPES  OF  SUGAR  BEETS 

A— Burned  off  by  stable  manure  unevenly  distributed  in  row.  B— Spiral  constrictions  on  beet.  C-Rapidly  taper- 
ing  beet  a  loss  in  tonnage.  D  Irregular  spiral  depressions  on  beets.  E — Irregular  growth  of  fibrous  roots. 


IO 


THE  COLORADO  EXPERIMENT  STATION 


8.  To  the  question  Do  Beet  Crops  Require  More  or  Less 

Water  than  Other  Field  Crops. 

38  per  cent,  said  more  water. 

30  per  cent,  said  less  water. 

31  per  cent,  said  same  as  other  crops 

9.  Value  01  after  Crop ,  Tops,  Etc. — In  answer  to  this, 
question,  65  per  cent,  placed  the  value  between  $2  and  $3  per  acre, 
while  the  average  value  assigned  was  $3  per  acre. 

10.  Tonnage  fdr  1904.  —  The  average  for  those  reporting 
was  17.4  tons  per  acre.  The  state  average  for  the  same  year  was. 
less  than  12  tons. 

11.  Tonnage  for  1095. —  The  average  yield  reported  was 
141^  tons  per  acre,  which  is  several  tons  above  the  estimated  aver¬ 
age  of  the  State.  This  would  indicate  that  1904  was  a  more  favora¬ 
ble  year  for  beet  culture  than  1905,  and  that  those  reporting  are 
among  our  most  successful  farmers  in  this  industry. 

12.  Expense  per  Acre. — The  expense  differed  according  to 
locality  from  $20  to  $50,  but  the  average  was  $33.05  per  acre. 

TABLE  No.  6. 


COST  OF  PRODUCTION. 


Average 
yield  per 
acre 
Tons 

Average 
cost 
growing 
per  acre. 

Total  in¬ 
come  per 
acre. 

Cost  of 
growing 
*ton  of 
beets. 

Total 
profit  per 
acre. 

Arkansas  Valley . . 

19.9 

$31.10 

$96.60 

$1.56 

$65.50 

Western  Slope  . 

17.7 

34.80 

85.20 

1.96 

50.40 

Northern  Colorado  . 

17.1 

36.43 

84.68 

2.13 

48.25 

*  Minus  the  tare. 

ij.  Net  Profit  of  the  Crop. — The  reports  varied  to  a  re¬ 
markable  degree,  from  nothing  to  $75.00  per  acre.  It  was  almost 
impossible  to  strike  an  average,  the  greater  number  reporting  be¬ 
tween  $40.00  and  $55.00  per  acre. 

14.  To  the  question  Number  op  Years  Beets  Have  Been 
Grown  on  the  Same  Ground  Without  a  Change  of  Crop? — The 
average  was  two  years.  However,  most  of  these  farmers  have  been 
growing  beets  but  two  years. 

15.  To  the  question  Do  You  Manure  Your  Beet  Land? — 
59  per  cent,  report  they  do,  41  per  cent,  report  they  do  not. 


CULTURAL  METHODS  FOR  SUGAR  BEETS 


II 


TABLE  No.  7. 

BEETS  GROWN  WITH  OR  WITHOUT  MANURE. 


YIELD,  TONS  PER  ACRE. 


With 

Manure 

Without 

Manure 

Arkansas  Valiev 

19  5 

17.5 

16.8 

14.2 

18.4 

15.3 

Western  Slope 

Northern  Colorado 

Average . 

17.9 

14.3 

This  table  shows  the  value  of  manure  for  the  beet  °rower. 
More  farmers  in  the  Aikansas  \  alley  are  using-  stable  manure  or 
fertilizers  than  either  of  the  other  sections  of  the  state. 


16.  Time  of  Pulling  Beets.  —  Time  of  pulling  beets  was 
reported  from  September  to  November,  the  great  majority  harvest¬ 
ing  in  October. 

ij.  The  per  cent,  of  Tare.  —  This  was  reported  from  1 

per  cent,  to  23  per  cent.  The  majority,  however,  was  less  than 
5  per  cent. 

•  Cause  of  Tare  75  cent,  of  the  farmers  reporting 
believed  it  was  due  to  the  dirt  clinging  to  the  beets  when  harvested. 
The  rest  attributed  it  to  defective  methods  of  harvesting  and  char¬ 
acter  of  crown  growth. 

/p.  Condition  of  Ground  at  Harvest  Time.  —  The  great 
majority  report  the  ground  very  dry  and  cloddy  at  pulling  time. 
This  is  largely  governed  by  climatic  conditions  beyond  the  beet 
farmer’s  control. 

20.  Is  the  Crop  a  Satisfactory  One?  —  80  per  cent,  of 
the  reporting  farmers  declare  it  to  be  the  most  profitable  crop  which 
they  can  grow.  The  following  statements  are  given  by  farmers  hav¬ 
ing  at  least  four  years  of  successful  experience  in  sugar  beet  culture: 

1.  The  sugar  beet  crop  is  an  expensive  one  to  grow  and  should  be 
grown  on  the  very  best  land  on  the  farm. 

.  2.  One  should  not  bring  to  the  surface  more  than  two  inches  of  new 
soil  in  plowing.  Ground  which  has  not  been  worked  holds  its  plant  food 
in  a  form  not  easily  available  to  the  plant.  The  young  beet  plant  does 
not  obtain  proper  nourishment  from  such  soil  and  is  checked  in  the  begin¬ 
ning  of  its  growth.  When  proper  conditions  prevail,  beet  ground  should 
be  plowed  at  least  10  to  12  inches  deep.  When  beet  land  is  plowed  in  the 
fall,  the  soil  is  weathered,  rendering  plant  food  at  surface  easily  available 
to  young  plants. 


12 


THE  COLORADO  EXPERIMENT  STATION 


3.  Beet  ground  should  be  as  uniformly  level  as  the  lay  of  the  land 
will  permit. 

4.  Early  planted  beets  have  generally  given  the  best  yields.  The 
seed  bed  should  be  warm,  Moist ,  but  not  wet,  for  the  best  germination. 

5  A  uniform  stand  is  seldom  obtained  when  seed  is  covered  more 
than  two  inches  deep.  The  vitality  of  the  beet  seed  does  not  seem  to  be 
sufficient  to  send  the  sprout  out  of  the  ground  from  greater  depths 
Moisture  conditions  must  indicate  the  depth  to  plant,  as  a  shallowcovered 
seed  makes  a  rapid  growth  with  proper  soil  and  moisture  conditions. 

fi  Earlv  thinning  of  beets  has  given  the  best  results,  since  young 
t>lants  recover  from  the  effects  of  the  thinning  process  without  too  serious 
a  delav  in  plant  growth.  The  beet  farmer  aids  in  the  thinning  process  by 
seeding  not  more  than  5  to  10  acres  at  one  time.  His  help  can  get  over 
his  entire  field  before  the  beets  are  too  large  for  successful  thinning. 

7  Cultivation  is  for  the  purpose  of  keeping  down  weeds,  prevent 
baking  of  the  surface  and  give  encouragement  to  continuous  development 

of  the  beets. 

8  The  iudicioususe  of  water  tends  to  produce  well  shaped  beets, 
increases  the'tonnage  and  gives  a  good  sugar  content,  when  proper  sun 
and  soil  conditions  prevail. 

9  Each  factory  furnishes  field  superintendents  who  are  assisting 
farmers  to  learn  the  efficient  use  of  water  in  sugar  beet  culture. 

10.  Beet  farmers  should  plan  for  at  least  four  weeks  of  the  growing 
season  after  the  last  irrigation  to  mature  the  crop. 


11.  The  Colorado  climate, sun  and  soils  are  well  adapted  to  sugar  beet 
culture.  This  industry  seems  destined  to  grow  with  the  development  of 
irrigation  in  the  state. 

12.  The  growing  of  beets  requires  a  crop  rotation  which  shall  main¬ 
tain  the  humus  and  plant  food  elements  in  the  soil.  In  Northern  Colorado 
where  sheep  feeding  is  carried  on  quite  extensively,  the  manure  is  care¬ 
fully  saved,  composted  for  a  year,  and  then  hauled  to  the  beet  lands. 

13.  A  practical  rotation  of  alfnlfa,  potatoes  or  other  cultivted  crop, 

beets  and  grain  is  being  gradually  adopted. 

14.  The  culture  of  sugar  beets  is.  improving  farm  methods  m  all 

crop  production. 

The  Station  has  planned  some  cultural  experiments  with  sugar 
beets  and  other  root  crops  for  the  seasons  of  1906,  1907  and  1908 
for  the  purpose  of  determining  the  best  methods  for  improving 
the  quality  and  increasing  the  tonnage  of  these  most  profitable 
crops.  Results  will  be  given  in  other  progress  bulletins. 


Bulletin  110 


April,  1906 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College 


ALFALFA 

(Results  Obtained  at  the  Colorado  Experiment  Station) 


By 


W.  P.  HEADDEN 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
FORT  COLLINS,  COLORADO 
1906 


THE  AGRICULTURAL  EXPERIMENT  STATION 


FORT  COLLINS.  COLORADO 


THE  STATE  BOARD  OF  AGRICULTURE 


Hon.  P.  F.  SHARP,  President ,  - 

Hon.  HARLAN  THOMAS,  -  -  - 

Hon.  JAMES  L.  CHATFIELD,  -  - 

Hon.  B.  U.  DYE,  -  -  -  - 

Hon.  B.  F.  ROCKAFELLOW,  -  - 

Hon.  EUGENE  H.  GRUBB  -  -  . 

Hon  A.  A.  EDWARDS,  -  -  -  - 

Hon.  R.  W.  CORWIN,  -  -  -  - 

Governor  JESSE  F.  McDONALD, 

President  BARTON  O.  AYLESWORTK, 

A.  M.  HAWLEY,  Secretary  EDGAR  AVERY,  Treasurer 


LE 

TERMS 

EXPIRES 

-  Denver, 

-  1907 

Denver, 

-  1907 

Gypsum, 

-  1909 

Rockyford, 

1909 

Canon  City 

-  1911 

-  Carbondale, 

-  1911 

Fort.  Collins, 

-  1913 

-  Pueblo 

-  1913 

ex-oTicio. 


EXECUTIVE  COMMITTEE  IN  CHARGE 

/  P.  F’  SHARP,  Chairman 


B.  F.  ROCKAFELLOW. 


A.  A.  EDWARDS. 


STATION  STAFF 

L.  G.  CARPENTER,  M.  S.,  Director ,  -----  -  Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S.,  -  -----  -  -  -  Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D.,  -  _____  Chemist 

W.  PADDOCK,  M.  S.,  -  -  -  -  -  -  -  Horticulturist 

W.  L.  CARLYLE,  M.  S.,  -  -  -  -  -  -  -  -  -  -  Agriculturist 

G.  H.  GLOVER,  B.S.,D.V.M.,  -  --------  Veterinarian 

W.  H.  OLIN,  M.  S.,  -  -  -  -  Agronomist 

R.  E.  TRIMBLE,  B.  S.,  -  -  -  -  -  Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S.,  -------  -  Assistant  Chemist 

EARL  DOUGLASS,  M.  S  ,  -  -  -  -  -  -  -  -  Assistant  Chemist 

A.  H.  DANIELSON,  B.  S.,  -  -  -  -  -  -  Assistant  Agriculturist 

S.  ARTHUR  JOHNSON,  M.  S.,  -  -  -  -  -  -  Assistant  Entomologist 

B.  O.  LONGYEAR,  B.  S.,  -  -  -  -  -  -  Assistant  Horticulturist 

J.  A.  McLEAN,  A.  B.,  B.  S.  A  ,  -  -  -  -  -  -  -  Animal  Husbandman 

E.  B.  HOUSE,  -  --  --  --  -  Assistant  Irrigation  Engineer 
P.  K.  BLINN,  B.  S.,  -  -  -  Field  Agent  Arkansas  Valley,  Rockyford 

Western  Slope  Fruit  Investigations,  Grand  Junction: 

O.  B.  WHIPPLE,  B.  A.,  -  -  --  --  -  -  Field  Horticulturist 

E.  P.  TAYLOR,  -  Field  Entomologist 


OFFICERS 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 


L.  G.  CARPENTER,  M.  S.,.  ----------  -  Director 

A.  M.  HAWLEY,  -  -  -  Secretary 


MARGARET  MURRAY,  -  -  Stenographer  and  Clerk 


ALFALFA 

(Results  Obtained  at  the  Golorado  Experiment  Station) 

BY 

•  ,  .  ’  •  •  i  »  «  '  ,  *  i 

W.  XL  IIXLFVOOILN 


r  -  *  .  .  .  •  .  •  *..»;  *  ♦ 

*  ...»  »  . 

It  has  frequently  been  suggested  to  the  writer  that  he  should  pre¬ 
pare  a  short  bulletin  on  alfalfa,  containing  many  of  the  facts  presented 
in  Bulletin  No.  35,  and  such  others  as  may  have  been  acquired  since 
its  publication. 

History.— This  plant  is  known  under  the  name  of  Medic,  Lucern 
and  Alfalfa.  The  latter  is  the  name  under  which  the  Arabs  intro¬ 
duced  it  into  Spain,  whence  it  was  brought  to  the  Americas.  The 
plant  with  its  Arabic  name  was  introduced  into  California  in  the  early 
fifties  by  the  Chilians,  and  thence  into  Colorado.'  ■  ' 

The  plant  has  been  known  since  490  B.  C.  at  least,  for  in  that  year 
it  was  introduced  into  Greece  under  the  name  of  Medic,  signifying 
that  it  came  from  Media.  A’  .. 

Culture.— The  methods  of  culture  are  quite  uniform  in  all  sections 
where  the  plant  is  grown,  and  all  the  data  collected  on  this,  subject 
show  -that  the  methods  now  followed  have  been  practiced  in  all  es¬ 
sential  features  for  centuries.  The  principal  points  are  a  well  pre¬ 
pared  seed  bed,  good,  plump  seed  planted  deep  enough  to  assure  ger¬ 
mination,  which  varies  with  the  climate  and  soil  from  very  shallow  to 
three  inches  deep.  The  common  practice  is  to  drill  in  the  seed  with  a 
protective  crop,  oats  or  spring  wheat.'  '  _ 

I  have  not  yet  seen  or  learned  of  alfalfa  having  been  grown  in 
drills  and  cultivated,  except  on  a  small  scale,  though  there  are  records 
of  such  a  practice  and  the  results  were  excellent.  The  plants  were  set 
six  inches  apart,  with  two  feet  between  the  rows,  and  when  cultivated 
and  manured  did  not  deteriorate  at  any  age.  The  latter  claim  may 
well  be  doubted,  but  observations  made  on  plants  growing  singly 
either  without  any,  or  with  a  pseudo-cultivation,  and  on  plants  grown 
in  single  drills  with  cultivation,  strongly  corroborate  the  claims  made 
for  the  practice. 


4 


Bulletin  110. 


Varieties. — The  varieties  of  alfalfa  experimented  with,  three 
French  varieties,  the  Turkestan  and  the  common  home  grown  seed, 
have  not  shown  material  differences  in  composition.  Whatever  dif¬ 
ferences  may  have  originally  existed  between  the  French  varieties 
practically  disappeared  under  our  conditions  of  soil  and  climate. 
This  was  not  the  case  with  the  Turkestan  which  was  very  uniform 
and  distinct  in  habit. 

There  are  few  plants  which  show  greater  individual  differences 
than  alfalfa  grown  from  our  home  grown  seed,  and  it  would  seem 
very  probable  that  we  could  develop  a  variety  superior  even  to  the 
Turkestan  by  a  little  patience  and  judicious  selection.  Our  common 
alfalfa  presents  two  types,  readily  recognized  by  the  growers;  one  has 
a  dark  green  color  and  narrow  leaves  with  red  stems  and  usually  deep 
violet  purple  flowers,  while  the  other  has  green  stems  and  much  lighter 
flowers.  The  former  is  leafier  and  earlier  than  the  latter,  but  is  pos¬ 
sibly  a  little  less  vigorous  grower.  In  the  color  of  its  leaves  and  habit 
of  plant,  the  former  resembles  the  Turkestan. 

Range  of  Soil  and  Altitude. — Alfalfa  thrives  in  all  of  our  Colorado 
soils  which  are  not  too  wet.  In  some  sections  it  is  short  lived  due  to 
winter  killing,  but  I  have  seen  fine  alfalfa,  on  good  soil  with  a  favorable 
aspect,  at  an  altitude  of  nearly  9,000  feet.  The  altitude  at  which  it 
will  do  well  varies  with  location  and  other  conditions. 

Amount  of  Water  Required. — Like  other  questions  pertaining  to  a 
general  practice  the  answer  is  difficult  to  give,  but  it  is  safe  to  assume 
that  it  will  require  from  twenty  to  twenty-four  inches  of  water  to  the 
acre  to  grow  the  three  crops  usually  cut  in  this  State. 

The  Time  of  Cutting. — The  first  cutting  is  usually  made  between 
early  bloom  and  half  bloom.  It  is  not  so  common  to  let  it  stand  till 
the  plant  is  in  full  bloom  as  it  was  at  one  time.  If  the  weather  is  fav¬ 
orable  the  first  cutting  is  made  as  early  as  possible  to  give  a  longer  sea¬ 
son  for  the  growing  of  the  second  and  third  cuttings.  Some  regard  is 
also  had  for  the  purposes  for  which  the  hay  is  to  be  used.  I  believe 
that  the  best  hay  for  feeding  purposes  is  obtained  by  cutting  when  the 
plant  is  in  full  bloom,  but  it  is  the  general  practice  to  cut  it  in  early 
bloom. 

Composition  of  Hay  Influenced  by  Condition  of  Plant  at  Time  of 
Cutting. — The  chemical  composition  of  the  hay  produced  is  not  so 
materially  affected  by  the  condition  of  the  plant  at  the  time  of  cut¬ 
ting  as  we  are  wont  to  think.  With  us  the  weather  exerts  a  big  in¬ 
fluence  on  the  rate  of  growth  and  early  blooming  of  the  plants,  this 
is  most  marked  in  the  second  cutting  in  which  the  condition  of  half 
bloom,  for  instance,  may  correspond  to  an  earlier  period  of  growth  in 
the  first  cutting,  so  far  as  composition  is  concerned. 

The  following  analyses  taken  from  Bulletin  39  of  this  Station, 
give,  I  believe,  a  fair  example  of  the  range  in  the  composition  of  alfalfa 
hay  as  affected  by  the  time  of  cutting. 


Alfalfa. 


5 


Cutting 

/ 

Condition  of 
the  Plants 

Air  Dried  Hay. 

Thoroughly  Dried  Hay 

Moisture 

Ash 

Ether 

Extract 

Crude 

Protein 

Crude 

Fiber 

l  • 

0 

<L  M 

£  ® 
-w  <L> 

•rH  fc. 

Total 

Nitrogen 

Ash 

Ether 

Extract 

Crude 

Protein 

Crude 

Fibre 

Nitrogen 

Free  Ext. 

a 

<X> 

b0 

o 

CO 

H 

2.624 

2.508 

2.687 

2.606 

1 

1 

1 

1 

Coming  in  bloom . 

In  half  bloom . 

In  full  bloom . 

Average . 

7.22 

7.92 

6.38 

7.17 

9.81 

11.89 

10.57 

10.76 

1.15 

1.26 

1.31 

1.24 

15.16 

14.46 

15.73 

15.12 

36.49 

32.8C 

34.91 

34.73 

30.17 

31.67 

31.11 

30.98 

2.426 

2.310 

2.516 

2.417 

10.57 

12.92 

11.29 

11.44 

1.24 

1.36 

1.40 

1.33 

16.47 

15.70 

16.80 

16.32 

39.43 

35.62 

37.29 

37.44 

32.29 

34.41 

33.23 

33.31 

2 

Coming  in  bloom . 

4,43 

12.70 

1.71 

17.68 

27.47 

36.01 

2.858 

13.28 

1.78 

18.50 

28.75 

37.69 

2.990 

2 

In  half  bloom . 

9.48 

1134 

1.50 

17.14 

24.27 

36.27 

2.743 

12.53 

1.65 

18.94 

26.81 

40.08 

3.032 

In  full  bloom . 

8.56 

9.91 

1.78 

16.41 

27.11 

36.24 

2.625 

10.84 

1.95 

17.94 

29.64 

39.64 

2  880 

2 

Average . 

7.49 

11.32 

1.66 

17.08 

26.28 

36.17 

2.742 

12.22 

1.79 

18.46 

28.38 

39.13 

2.967 

3 

Coming  in  bloom . 

8.64 

12.24 

1.72 

16.53 

24.30 

36.57 

2.645 

13.39 

1.88 

18.09 

26.59 

40.04 

2.894 

3 

In  half  bloom . 

7.43 

11.07 

1.52 

15.52 

30.55 

33.92 

2.482 

11.96 

1.64 

16.76 

33.00 

36.65 

2.681 

3 

In  full  bloom . 

8.36 

10.66 

1.83 

15.59 

30.18 

33.38 

2.495 

11.63 

2.00 

17.01 

32.94 

36.42 

2.722 

Average . 

8.14 

11.32 

1.69 

15.88 

28.34 

34.62 

2.540 

12.33 

1.84 

17.29 

30.84 

37.70 

2.766 

For  a  large  number  of  analyses  and  a  discussion  of  the  individual 
groups  or  fodder  constituents  see  Bui.  35,  p.  90,  also  pp.  13-25. 

Relative  Value  of  the  Different  Cuttings  of  Alfalfa. — I  have  stated 
in  a  preceding  section  that  the  usual  practice  is  to  cut  alfalfa  when  it 
has  not  yet  advanced  to  the  stage  of  half  bloom,  though  it  is  my  opin¬ 
ion  that  the  best  general  purpose  hay  is  obtained  by  cutting  it  when 
it  is  in  full  bloom.  There  are  good  reasons  why  the  practice  of  cut¬ 
ting  it  when  in  early  to  half  bloom  has  come  to  be  so  generally  adopted, 
but  these  reasons  do  not  effect  the  subject  discussed  in  this  para¬ 
graph.  I  have  also  given  the  composition  of  the  first,  second  and 
third  cutting  taken  at  the  periods  of  coming  into  bloom,  in  half 
bloom  and  in  full  bloom,  from  which  it  appears  that  the  extreme  dif¬ 
ferences  in  the  composition  of  alfalfa  hay  are  less  than  they  are  fre¬ 
quently  assumed  to  be.  This  fact  explains  the  varying  opinions  held 
in  regard  to  their  relative  values.  There  are  some  differences  in  com¬ 
position  but  they  are  not  big  enough  to  produce  the  differences  which 
come  under  the  notice  of  the  feeder.  The  analyses  given  in  the 
preceding  table,  in  my  judgment, faithfully  represent  the  composition 
of  good  Colorado  alfalfa  hay  grown  under  average  conditions  for 
Northern  Colorado.  That  the  analyses  given  really  represent  the 
composition  of  Colorado  alfalfa  hay  is  evident  from  the  following  ana¬ 
lysis  which  is  the  average  obtained  for  the  first  cutting  for  three 
consecutive  years;  moisture,  6.86;  ash,  10.65;  fat,  1.54;  protein, 
15.00;  crude  fibre,  33.29;  nitrogen-free  extract,  32.12. 

The  above  average  is  obtained  from  19  closely  agreeing  analyses 
of  first  cutting  alfalfa  hay. 


6 


Bulletin  110. 


In  the  analyses  given  in  the  table  it  will  be  noticed  that  the  great¬ 
est  difference  in  the  percentage  of  protein  is  1.27  per  cent  and  this  is 
in  favor  of  the  sample  taken  when  in  full  bloom  over  the  one  cut  in 
half  bloom.  We  are  justified  in  assuming  that  the  preceding  analyses 
are  thoroughly  representative  of  the  composition  of  alfalfa  hay  cut 
at  these  different  periods,  and  we  will  neglect  any  error  introduced 
by  assuming  that  the  whole  of  the  nitrogen  is  present  as  proteid 
and  consequently  all  of  equal  value.  In  the  analyses  given  it 
appears  that  the  hay  cut  when  the  plants  were  in  full  bloom  con¬ 
tains  the  largest  percentage  of  proteids.  We  have  so  many  analyses 
showing  this  to  be  the  case  in  our  samples,  that  we  believe  that  it  is 
true  for  alfalfa  hay  grown  under  the  average  conditions  obtaining  in 
Northern  Colorado.  The  difference  is  seldom  so  great  as  that  shown  by 
the  hay  cut  in  half  bloom  and  full  bloom  in  the  analyses  given.  In 
the  samples  given  each  100  pounds  of  the  thoroughly  dried  hays 
would  contain  16.5,  15.7,  and  16.8  pounds  respectively  according  to 
which,  if  the  proteids  alone  be  the  standard  of  value,  the  hay  cut  in 
full  bloom  is  the  best,  but  pound  for  pound  they  are  as  I  have  before 
stated  almost  equal.  While  this  series  of  analyses  gives  these  results 
others  will  show  the  earlier  cut  hays  to  have  slightly  the  advantage. 
But  chemical  composition  is  not  the  only  consideration  to  be  taken 
into  account.  The  weight  of  hay  cut  off  of  an  acre  at  full  bloom  i§~ 
considerably  more  than  the  same  acre  would  yield  if  cut  in  early  or 
half  bloom,  probably  from  10  to  15  per  cent  more.  Regarding  the 
degestibility  of  the  hays  made  at  the  different  stages  of  growth,  using 
the  proteids  as  our  criterion)  because  we  assume  them  to  be  the  most 
valuable  constituent,  experiments  show  them  to  be  very  nearly  alike, 
with  a  slight  difference  in  favor  of  the  hay  cut  at  full  bloom. 

We  found  the  coefficient  of  digestion  of  the  proteids  in  hay  cut  at 
the  period  of  half  bloom,  by  artificial  digestion,  to  be  79.30  and  79.60 
and  by  animal  digestion  73.7,  73.6  and  70.4.  Artificial  digestion  seems 
to  be  fairly  reliable  though  a  little  too  high.  The  error,  however,  is 
likely  to  be  in  the  same  direction  in  the  case  of  both  samples,  if  so  the 
hay  cut  at  full  bloom  is  slightly  preferable. 

As  soon  as  alfalfa  passes  the  stage  of  full  bloom  there  is  a  decided 
fall  in  the  amount  of  proteids  present,  the  same  is  true  of  the  nitrogen 
free  extract..  The  loss  of  proteids  amounts  to  about  2.5  per  cent 
of  the  weight  of  the  hay  and  the  proteids  are  according  to  the  results 
obtained  by  artificial  digestion  less  digestible  than  at  either  early,, 
half  or  full  bloom. 

Effects  of  Differences  in  the  Seasons. — That  there  are  differences 
in  the  hay  from  season  to  season,  within  comparatively  narrow  limits 
of  course,  due  to  the  distribution  of  rainfall  and  variations  in  temper¬ 
ature,  is  a  fact  generally  recognized.  In  speaking  of  this  subject  in 
Bui.  No.  39  I  conclude  from  a  series  of  samples  taken  over  a  period  of 
three  years  and  representing  hay  grown  on  four  different  soils,  that, 
the  composition  of  the  first  cutting  is  practically  constant  while  that 
of  the  second  and  third  cuttings  is  much  less  so,  and  in  the  latter  we  } 
probably  find  the  maximum  variation  that  can  reasonably  be  attribu- 


•  Alfalfa.  7 

ted  to  the  differences  in  the  seasons.  These  differences  amount  to  three 

PuP  for  CT,U(\er  protein,  eight  per  cent  for  the  crude  fibre  and 
about  three  and  a  half  per  cent  for  the  nitrogen  free  extract. 

t  1 1  Easily  InJured  by  Moisture. — In  Cases  where  the  al¬ 

falfa  has  been  cut  and  left  in  the  swath,  a  light  rain  of  even  a  heavy 
dew  produces  a  discoloration.  The  hay  has  a  light  yellowish  brown 
color  and  in  general  a  bleached  appearance.  The  amount  of  injury 
indicated  by  this  color  doubtlessly  varies  greatly  and  there  is  a  variety 
of  opinion  about  the  value  of  such  hay.*  In  one  instance  in  which 
some  all  alt  a  was  cut  and,  owing  to  a  succession  of  showers,  was  not 
stacked  till  13  days  later,  we  found  very  considerable  changes,  but  we 
were  not  able  to  determine  the  total  changes,  for  we  were  unable  to  de¬ 
termine  the  mechanical  loss  in  the  weight  of  the  hay.  The  differences' 
shown  by  the  analyses  of  samples  taken  as  the  hay  was  cut,  and  of 
others  taken  as  it  was  stacked,  showed  a  loss  of  more  than  one-third 
ot  the  crude  protein  and  one  seventh  of  nitrogen  free  extract,  accom¬ 
panied  by  a  very  decided  increase  in  the  crude  fiber,  the  percentage 
found  m  the  injured  hay  being  about  12  per  cent  higher  than  in  the 
uninjured  sample.  The  amount  of  rainfall  was  about  1%  inches. 
Experiment  shows  that  tepid  water  will  dissolve  40.00  per  cent  out  of 
c  ass>  third  cutting  alfalfa  hay;  further,  fermentation  sets  in 
readily.  These  properties  readily  explain  the  fact  that  alfalfa  is  very 
sensitive  to  moisture.  The  remaining  hay  may  still  be  good  hay, 
though  its  color  is  not  inviting.  There  may,  however,  have  been  a 
big  loss,  the  remaining  hay  weighing  possibly  only  a  little  more  than 
six-tenths  as  much  as  should  have  been  gathered,  from  the  crop  as 

cut,  not  reckoning  any  mechanical  loss,  which  will  certainly' have  tak¬ 
en  place. 

Loss  of  Leaves,  Etc.,  in  Making  Alfalfa  Hay. — The  general  custom 
in  this  part  of  Colorado  is  to  rake  the  alfalfa  into  windrows  as  soon 
after  cutting  as  is  at  all  advisable,  and  complete  the  necessary  cur¬ 
ing  m  windrow  or  cock  as  the  case  may  be.  This  practice  is  the  re- 
suit  of  the  observed  loss  of  leaves  and  breaking  off  of  small  stems  in 
raking  and  handling,  if  allowed  to  over  cure  in  the  swath.  The  loss, 
that  is  the  leaves  and  stems  which  fall  or  are  broken,  amounts  under 
favorable  circumstances,  to  about  one-fifth  of  the  crop,  and  can  if  it. J 
^L-1^iCeSSar'^  rePeatedly  handle  the  hay,  amount  to  as  much  as  two- 
thirds  of  the  crop,  which  of  course  remains  on  the  ground  to  enrich  it. 

The  Relation  of  Hay  Gathered  to  Green  Alfalfa.— The  amount,  or 
weight  of  hay  gathered  compared  to  that  of  the  green  alfalfa  varies* 
within  comparatively  narrow  limits.  With  us  100  pounds  of  first  cut¬ 
ting  alfalfa  gives  about  2/  pounds  of  hay,  and  100  pounds  of  second 
cutting  gives  about  29  pounds.  These  figures  do  not, agree  at  all 
with  figures  obtained  for  other  States.  The  amount  of  hay  obtained  * 
from  100  pounds  of  the  green  alfalfa,  cut  from  early  bloom  to  full 
bloom,  has  an  extreme  range  of  about  four  pounds.  This  is  the  case 
with  the  first  and  second  cuttings. 

The  Relative  Amounts  of  Leaves  and  Stems.— Some  varieties  of 
alfalfa  are  smaller  stemed  and  leafier  than  others.  The  Turkestan 


8 


Bulletin  110. 


alfalfa  as  it  grows  with  us  is  much  leafier  than  our  common  alfalfa. 
Individual  plants  differ  in  this  respect  as  much  as  the  recognized  var¬ 
ieties  so  it  is  a  difficult  matter  to  obtain  any  figures  which  may  be 
applicable  except  in  individual  cases.  The  best  figures  that  we  have 
been  able  to  arrive  at  relatively  to  this  subject,  is  that  the  leaves 
seldom  if  ever  equal  less  than  40  per  cent  of  the  weight  of  the  plant, 
and  frequently  make  up  60  per  cent  of  the  weight  of  the  plant.  _  I  he 
rest  of  the  plant  is,  of  course,  represented  by  the  stems.  This  is  an 
important  consideration,  for  I  have  seen  hay  which  has  lost  a  very 
large  proportion  of  its  leaves  before  it  was  put  into  stack. 


Importance  of  Saving  the  Leaves  in  Making  Alfalfa  Hay.— The 

preceding  paragraph  shows  that  we  are  justified  in  assuming  that 
one-half  of  the  weight  of  the  plant  as  cut,  is  represented  by  the  leaves. 
The  importance  of  this  fact  in  hay  making  becomes  very  apparent 
when  we  further  learn  that  nearly  four-fifths  of  the  crude  protein  con¬ 
tained  in  the  plant  is  found  in  the  leaves,  and  only  one-fifth  in  the 
stems.  The  leaves  also  contain  considerably  over  one-halt  ot  the 
nitrogen  free  extract  and  fat,  while  the  stems  contain  nine-elevenths  ot 
the  crude  fiber.  It  appears  from  these  facts  that  the  leaves  contain 
very  considerably  more  than  half  of  those  matters  which  we  consider 
as  of  the  most  value  as  fodder  constituents,  i.  e.,  the  crude  protein, 
nitrogen  free  extract  and  fat,  on  the  other  hand  the  stems  contain 
almost  3-4  of  the  crude  fiber. 

This  statement  of  these  facts  brings  out  the  wisdom  ot  the  prac¬ 
tice  of  raking  the  alfalfa  into  windrows  as  soon  after  cutting  as  is  at 
all  feasible,  and  stacking  or  putting  it  into  the  mow  with  as  little  hand¬ 
ling  as  possible. 


The  Composition  of  Alfalfa  Stems  and  Leaves.— It  sometimes  hap¬ 
pens  that  the  leaves  are  very  largely  shaken  off,  and  the  hay  consists 

principally  of  the  stems.  I  have  seen  such  in  the  cock  which  was  not 
unlike  fine  brush.  The  leaves  in  such  cases  are  evidently  lost  as  far 
as  the  hav  making  is  concerned,  but  the  stems  make  a  fair  hay,  too 
good  to  be  neglected,  which  is  evident  from  their  composition  which 
is  given  below,  together  with  analyses  of  timothy  and  native  hays 


and  alfalfa  leaves. 


Alfalfa  Stems  . 

Timothy  Hay  (Colo.) 
Timothy  Hay  (Colo) 
Native  Hay  (Colo.) . . 
Alfalfa  Leaves . . 


Moisture 

Ash 

Fat 

Protein 

Fibre 

Nitrogen- 
Free  Extract 

.  .5.71 

4.99 

0.85 

6.35 

54.32 

27.79 

.  ..6.49 

9.34 

2.99 

5.62 

31.54 

43.99 

.  .6.58 

7.21 

1.43 

7.45 

40.71 

36.52 

.  .5.13 

10.64 

3.13 

6.98 

31.38 

42.74 

. .  .4.93 

14.48 

2.96 

23.33 

13.15 

41.16 

The  leaves  are  lost,  it  is  true,  so  far  as  making  hay  is  concerned 
but  they  add  materially  to  the  betterment  of  the  soil.  We  never 
have  hay  consisting  mostly  of  leaves,  but  in  feeding  sheep  and  cattle 
it  is  observed  that  they  seem  to  prefer  the  leaves,  and  there,  is  often 
a  considerable  portion  of  stems  left.  The  preceding  analysis  shows 
that  these  stems  are  good  fodder  and  a  horse  will  eat  them  readily. 
The  composition  of  the  leaves  is  given  in  the  preceding  table. 


Alfalfa. 


9 


Alfalfa  Requires  Water  to  Make  a  Good  Growth.— Our  average 
rainfall  may  be  taken  at  14  1-2  inches.  In  addition  to  this  it  requires 
from  6  to  8  inches  of  water  per  acre  to  grow  the  three  crops  usually 
cut  in  this  section.  Alfalfa  is  a  deep  rooted  plant  and  will  live  when 
once  established  on  high  land  even,  with  the  addition  of  a  small  amount 

of  water,  but  it  needs  the  above  amount  of  water  to  make  a  good 
growth. 

Alfalfa  Ensilage.— The  considerable,  unavoidable  loss  incurred 
m  making  alfalfa  hay,  say  from  17.5  to  60  per  cent  of  the  crop,  togeth¬ 
er  with  the  desirability  of  having  some  succulent  fodder,  has  led  to 
experiments  in  making  alfalfa  silage.  The  silage  is  good  and  is  read¬ 
ily  eaten  by  cattle,  the  following  analyses  may  be  taken  as  represent¬ 
ing  its  composition;  moisture,  8.98;  ash,  13.19;  ether  extract,  fat 
2.93;  crude  protein,  14.18;  crude  fiber,  30.77  and  nitrogen  free  extract 
29.95  per  cent. 

Plant  Food  Required  to  Grow  a  Crop  of  Alfalfa.— The  excellent  re¬ 
sults  observed  to  follow  putting  land  down  to  alfalfa  for  three  or  more 
years,  leads  to  the  conclusion  that  it  enriches  the  soil.  In  a  cer¬ 
tain  sense  this  is  the  case,  and  the  practice  of  seeding  run-down  land 
to  alfalfa  and  leaving  it  in  alfalfa  for  several  years  before  breaking  it 
up  again  to  plant  other  crops,  has  been  the  salvation  of  this  section 
of  Colorado,  and  yet  it  does  not  follow  that  the  alfalfa  plant  does  not 
require  a  large  amount  of  plant  food.  The  average  percentage  of 
crude  ash  in  alfalfa  hay  is  not  far  from  10.00  per  cent,  or  in  a  crop  of 
4  1-2  tons,  9,000  pounds,  there  will  be  900  pounds  of  crude  ash,  which 
will  contain  39.10  pounds  of  phosphoric  acid,  231.5  pounds  of  potash 
(K20),  62.8  pounds  of  chlorin,  208.8  pounds  of  lime  (CaO). 

There  are  but  few  crops  which  will  equal  the  alfalfa  in  its  draft 
upon  the  resources  of  the  soil  in  which  it  grows,  but  while  other  crops 
gather  their  food  from  a  depth  of  two,  four  or  five  feet,  alfalfa  gathers 
its  food  from  depths  ranging  from  six  to  twelve  feet — so  on  the  assump¬ 
tion  that  the  alfalfa  plant  has  no  greater  power  to  gather  its  food  than 
the  wheat  plant,  for  example,  it  has,  owing  to  the  greater  depth  to 
which  its  roots  penetrate,  from  three  to  four  times  the  depth  of  soil 
to  feed  on.  This  is  an  essential  advantage,  especially  if  the  upper 
portions  of  the  soil  from  which  the  wheat  plant  has  to  draw  its  food 
has  already  been  partially  exhausted  by  repeated  cropping,  as  has 
been  the  case  in  many  instances  in  this  State. 

Most  of  our  cultivated  plants  depend  wholly  upon  the  nitrogen 
stored  in  the  soil  for  their  supply,  the  alfalfa  plant  does  so  only  in  part, 
drawing  a  portion  of  its  supply  from  the  atmosphere.  Though  it 
may  gather  large  amounts  of  this  element  from  the  soil,  it  probably 
returns  more  in  the  leaves  that  fall  and  the  plants  that  die  than  it 
takes  from  the  soil. 

Benefits  Accruing  to  the  Soil.— The  statements  of  the  preceding 
paragraph  may  seem  somewhat  contradictory  to  one  another,  and 
apparently  contradictory  to  what  is  an  acknowledged  and  well  estab¬ 
lished  fact,  i.  e.,  that  cropping  to  alfalfa  benefits  our  soils,  and  does  not 
exhaust  it  as  one  would  infer  from  the  amount  of  potash  (K2O)  for  in- 


10 


Bulletin  110. 


stance,  which  it  removes.  That  the  plant  requires  a  large  supply  of 
plant  food  is  very  evident,  for  we  find  it  contained  in  the  plant,  but 
its  little  feeding  roots  which  gather  this  food  are.  almost  wholly  below 
the  depth  at  which  ordinary  crops  feed,  so  this  portion  of  the  soil 
is  resting  while  in  alfalfa.  Many  of  the  plants  die  and  rot,  adding 
organic  matter  to  the  soil  and  facilitating  the  solution  of  the  mineral 
constituents  used  by  other  plants.  Not  only  do  the  plants  die  out, 
as  is  to  be  observed  in  almost  any  field  of  alfalfa,  though  I  have  seen 
some  in  which  this  was  not  apparent,  but  every  crop  grown  adds 
materially  to  the  upper  soil  by  that  portion  of  the  plant  which  escapes 
being  gathered  as  hay. 

The  Value  of  the  Stubble. — The  amount  of  leaves  and  stems  which 
fall  and  rot  on  the  surface  of  the  soil  each  year  is  always  considerable, 
and  is,  moreover,  high  in  manural  value,  but  the  addition  of  fertiliz¬ 
ing  substances  to  the  soil,  which  is  effected  by  planting  to  alfalfa,  is 
perhaps  more  strikingly  set  forth  by  the  facts  pertaining  to  the  value 
of  the  stubble.  The  stubble  of  alfalfa  taken  to  a  depth  of  6  1-2  inches, 
assuming  an  ordinary  stand,  weighs  nearly  6  tons  and  contains  over 
36  pounds  of  nitrogen,  equ.al  to  about  216  pounds  of  sodic  nitrate, 
Chili  saltpetre,  in  addition  to  8  1-3  pounds  of  phosphoric  acid  and 
15  1-2  pounds  of  potash.  The  alfalfa  roots,  however,  reach  a  depth 
of  9,  10  and  even  12  feet,  on  account  of  which  the  whole  root  system 
of  the  alfalfa  can  safely  be  credited,  with  twice  as  much  nitrogen, 
etc.,  as  is  found  in  the  stubble  taken  to  a  depth  of  6  1-2  inches.  The 
commercial  value  of  this  material  is,  at  present  prices,  upwards  of 
$35.00  per  acre. 

Stand  of  Alfalfa. — This  means  the  number  of  plants  in  a  given 
area,  I  believe  that  one  plant  to  the  square  foot  will  grow  as  much  hay 
and  of  as  good  a  quality  as  any  number  of  plants.  We  have  deter¬ 
mined  the  number  of  plants  to  the  acre  in  a  few  instances  and  found 
it  to  range  from  70,000  to  653,000.  The  hay  cut  from  the  field  with 
seventy  thousand  plants  was  as  desirable,  and  so  far  as  one  could 
judge  from  the  appearance  of  the  hay,  as  fine  as  that  cut  from  a  field 
having  562,000  plants  to  the  acre,  but  if  one  considers  the  benefit  to 
accrue  to  the  soil  the  thicker  stand  is  to  be  preferred,  for  there  will 
be  more  roots  to  penetrate  the  soil  and  their  aggregate  weight  will  be 
greater  while  they  will  penetrate  the  soil  to  quite  as  great  a  depth.  I 
have  dug  out  a  seedling  alfalfa  plant  nine  months  old  whose  root 
measured  9  1-3  feet,  while  its  diameter  at  the  crown  was  a  little  more 
than  one  quarter  of  an  inch.  The  stand  in  this  case  was  very  good, 
probably  not  less  than  400,000  plants  to  the  acre.  The  soil  in  this 
case  was  an  open  sandy  loam  and  very  deep. 

Alfalfa  Seed. — This  seed  varies  considerably  in  size  but  the  ger¬ 
minating  power  is  usually  high.  The  vigor  of  a  young  plant  from  a 
plump,  mature  seed  is  probably  greater  than  that  of  a  plant  from  a 
small,  shrunken,  immature  one,  but  the  germinating  power  of  even 
immature  seeds  is  high  and  their  vitality  is  far  greater  than  given  in 
Bui.  No.  35./  The  statements  made  in  it  were  .quite  contrary  to  the 


Alfalfa. 


11 


views  entertained  at  the  time  they  were  made,  but  are  very  conserva¬ 
tive  in  the  light  of  the  facts  obtained  since  that  time.  The  alfalfa 
seed  in  the  highest  state  of  perfection  that  I  have  seen  it  grown  in 
Colorado,  is  of  a  greenish  yellow  color  which  it  retains  with  but  little 
change  for  years.  I  have  some  which  I  gathered  12  years  ago  and 
it  is  but  little  less  bright,  if  any,  than  it  was  when  I  gathered  it.  I 
recently  showed  this  seed  to  an  expert  in  these  matters  who  scarcely 
believed  that  it  was  not  fresh  seed  and  who,  furthermore,  declared 
that  he  had  never  before  seen  such  alfalfa  seed.  I  believe  that  we 
seldom  obtain  alfalfa  seed  which  has  attained  its  highest  state  of  per¬ 
fection.  I  quite  recently  purchased  a  sample  of  the  best  alfalfa  seed 
obtainable  in  the  open  market  and  by  actual  count  there  is  only  10 
per  cent  of  this  sample  nearly  equal  to  the  run  of  the  12  year  old  sam¬ 
ple  referred  to  above.  The  sample  was  purchased  as  choice  seed  at 
15  cents  per  pound  but  the  individual  seeds  were  actually  smaller 
than  those  in  two  samples  of  first  quality  screenings  obtained  ten  years 
ago  and  grown  at  Rockyford,  Colorado.  The  first  quality  seed  pur¬ 
chased  last  season,  1905,  run  288,267  seeds  to  the  pound,  while  the 
samples  of  screenings  run  259,340  and  266,233  to  the  pound  respec¬ 
tively.  The  screenings  are  shriveled,  probably  because  these  seeds 
were  immature  when  the  plants  were  cut,  and  the  plump,  mature 
seeds  have  been  separated  by  screening  and  winnowing. 

The  Average  Yield  of  Alfalfa  Seed.— This  is  not  above  five  bushels 
per  acre.  A  yield  of  9  or  10  bushels  is  a  big  one  and  above  this  is  excep¬ 
tional.  I  have  heard  of  as  much  as  14  bushels  having  been  gathered, 
but  a  gentleman  of  large  experience  in  growing  alfalfa  seed  informs 
me  that  such  a  yield  is  very  exceptional. 

The  Vitality  of  Alfalfa  Seed. — Sometimes  we  fail  to  obtain  a  good 
stand  of  alfalfa,  even  though  we  use  the  amount  of  seed  per  acre 
which  experience  has  shown  to  be  sufficient,  say  20  pounds  to  the 
acre.  Such  failures,  a  few  years  ago,  were  usually  attributed  to  the 
lack  of  vitality  in  the  alfalfa  seed, especially  if  the  seed  were  a  little 
old.  It  _was  claimed  that  seed  two  or  more  years  old  had  already  so 
far  lost  its  vitality  as  'to  be  so  good  as  worthless.  This  notion  has 
prevailed  a  long  while.  Loudon  says  on  this  subject :  “Great  care 
should  be  had  to  procure  it  (Lucern  seed)  plump  and  perfectly  new, 
as  two  year  old  seed  does  not  come  up  freely.”  The  following" state¬ 
ment  is  made  in  North  Carolina  Bulletin  No.  60:  “The  vitality  of 
Lucern  seed  is  so  low  that  seed  over  one  year  old  is  scarcely  worth 
sowing.”  This  statement  is  supported  by  two  sprouting  experi¬ 
ments  .made  with  two  year  old  seed,  in  one  of  which  6  per  cent  and  in 
the  other  12  per  cent  germinated. 

.  *  1  showed  in  Bui.  No.  35  of  this  station,  pages  41-44,  that  this  is  a 
mistake.  I  recorded  on  page  43  of  Bui.  No.  35  the  result  of  22  ex¬ 
periments  in  which  I  used  11  samples  of  seed  ranging  in  age  from  one 
to  six  years.  The  11  samples  have  been  preserved  and  two  series  of 
experiments  have  been  made  with  them  since  that  time  at  intervals 
of  four  and  six  years — giving  me  a  range  in  the  age  of  the  seed  from 
11  to  16  years. 


12 


Bulletin  110. 


Some  of  the  samples  (two)  were  kept  in  envelopes,  the  rest 
were  kept  in  the  specimen  tubes  in  which  they  were  put  for  the  first 
experiment.  During  the  first  four  years  the 
in  a  table  drawer  in  my  sitting  roonp  and  for  the  last  six  years 
room  in  the  basement  of  the  chemical  laboratory. 

I  will  give  the  three  series  of  experiments  though  the  limits  of 

this  bulletin  scarcely  justify  it. 

No.  1.  Prime  seed  gathered  by  myself. 

No.  2.  Prime  seed  purchased  of  Vandewark. 

No.  3.  Prime  seed  purchased  of  P.  Anderson  &  Company. 

No.  4.  Prime  seed  furnished  by  J.  E.  Gauger. 

No.  5.  Prime  seed  furnished  by  J.  E.  Gauger. 

No.  6.  Prime  seed  purchased  of  P.  Henderson  &  Company. 

No!  7.  Screenings,  first  quality,  J.E.  Gauger. 

No.  8.  Screenings,  first  quality,  J.  E.  Gauger. 

No.  9.  Screenings,  first  quality,  J.  E.  Gauger. 

No.  10.  Screenings,  second  quality,  J.E.  Gauger. 

No.  11.  Screenings,  third  quality,  J.  E.  Gauger  ^  N  ok 

The  following  table  of  results  is  reproduced  from  Bui.  No.  d5, 
ynge  43. 

Tnr.RTTLTS  OF  SPROUTING  EXPERIMENTS  1896 


No  of 
Sample 

Quality 

Years  Old 

Number  of 
Seeds 
to  the 
Pound 

Seeds 

Taken 

Seed 

Rotted 

Seeds  Left 

Seeds 

Sprouted 

Average 

per  cent 

Sprouted 

2 

206,837  \ 

100 

100 

0 

0 

0 

8 

100 

92 

}  96.0 

1 

9 

2 

228,818  \ 

100 

100 

1 

0 

9 

6 

90 

94 

}  92.0 

Q 

Q 

208,021  \ 

100 

loo 

100 

100 

1 

1 

7 

0 

92 

99 

\  95.5 

O 

2 

. 5 

1 

5 

13 

5 

86 

90 

}  88.0 

4 

3 

. { 

100 

100 

0 

0 

2 

1 

98 

99 

\  98.5 

u 

6 

. { 

100 

100 

5 

5 

1 

3 

94 

92 

}  93.0 

b 

7 

8 

Q 

1 

259,340  \ 

100 

100 

23 

20 

11 

13 

66 

67 

}  66.5 

screenings,  ilisl  quality . 

2 

344,123  \ 

100 

100 

42 

29 

7 

11 

51 

60 

}  55.5 

screenings,  mst  quaiivij . 

3 

266,233  j 

100 

100 

24 

16 

1 

1 

75 

83 

}  79.5 

screenings,  mst  . . 

2 

331,383  j 

100 

100 

59 

53 

7 

5 

CO  ^ 

£  38.0 

1U 

11 

bcreenmgs.  seeuuu  . . 

1 

312,385  | 

100 

100 

66 

48 

1 

5 

33 

47 

f  8  .5 

11 

screenings,  liiiiu.  quantj .  •• 

The  results  in  this  table  show  conclusively  that  neither  of  the 
requisites  laid  down  by  Loudon,  that  is,  plump  and  new  seed,  are 
necessary  so  far  as  their  germinating  power  is  concerned  and  that  the 
statement  that  two  year  old  seed  do  not  germinate  freely,  to  say 


t 


Alfalfa. 


13 


nothing  about  the  more  extreme  statement  “that  they  are  scarcely 
worth  sowing,”  is  altogether  a  mistake. 

The  screenings  are  composed  of  the  small,  immature  and  shrunk- 
en  seeds.  These  seed  are  nearly  all  dark  brown  or  green  and  shriv- 
eled— probably  due  to  two  causes;  first  because  they  were  harvested 
while  still  very  immature  and  second  because  they  are  infested  with 
molds,  at  least  molds  develop  readily  during  the  sprouting  experi¬ 
ments  and  many  of  the  seed  rot,  but  as  the  table  shows  such  seed  ger¬ 
minate  freely  even  when  two  and  three  years  old.  Two  years  old 
screenings  show  a  germinating  power  of  38.0  and  55.5  per  cent,  respec¬ 
tively,  while  a  sample  of  three  years  old  screenings  shows  a  germina¬ 
tion  equal  to  79.0  per  cent.  The  variation  in  the  quality  of  the 
screenings  from  year  to  year  is  shown  by  the  varying  number  of  seeds 
to  the  pound,  which  in  the  screenings  of  some  years  is  smaller  than 
that  for  seed  sold  as  prime  seed  in  other  years. 

The  preceding  table  shows  that  a  large  percentage  of  the  screen¬ 
ings  rotted  and  that  the  percentage  of  seeds  which  rotted  did  not  de¬ 
pend  upon  the  age  of  the  screenings  but  upon  the  samples  themselves 
or  the  degree  m  which  the  samples  were  infested  with  the  cause  of  the 
rot.  It  is  strikingly  evident  from  the  table  that  none  of  the  clean, 
hand-picked  seed  No.  1  rotted  and  only  a  few  of  any  samples  of  prime 
seed,  while  as  high  as  59  and  66  per  cent  of  the  second  and  third 
quality  screenings  rotted.  This  rotting  is  most  probably  due  to  the 
fact  that  these  seed  were  already  infested  by  the  bacteria  and  other 
organisms  causing  it  before  they  were  threshed.  The  samples  of 
prime  seeds  and  of  screenings  will  not  serve  for  the  purpose  of  com¬ 
parison  from  this  point  of  view,  because  they  are  from  different  sour¬ 
ces  with  possibly  two  exceptions. 

I  have  observed,  particularly  in  my  last  experiments,  that  when  the 
seed  rot,  the  screenings  of  samples  10  and  11  for  instance,  they  appear 
to  be  glued  together  in  bunches  of  three  and  four  seeds  unless  they 
have  been  very  carefully  distributed  and  that  any  sprout,  however 
vigorous  and  bright,  is  attacked  and  distroyed  if  it  comes  in  contact 
with  such  a  mass.  The  colorless  mucilagenous  mass  enveloping  the 
seeds  is  crowded  with  bacteria. 

The  samples  of  seeds  used  in  the  following  experiments  are  the 
same  samples  used  in  1896  except  No.  12  of  the  series  of  1906. 


RESULTS  OF  SPROUTING  EXPERIMENTS— 1900 


No.  of 

Sample.  Quality. 

1  Prime  seed . 

2  Prime  seed . 

3  Prime  seed  . 

4  Prime  seed . 

5  Prime  seed . 

6  Prime  seed . 

7  Screenings,  first  quality  . 

8  Screenings,  first  quality  . 

9  Screenings,  first  quality  . 

10  Screenings,  second  quality 

11  Screenings,  third  quality  . 


Age  in 

Seeds  per 

Percent. 

Years. 

Pound. 

Germinating. 

6 

206,837 

92 

6 

228,818 

80 

6 

208,821 

70 

6 

78 

7 

66 

10 

72 

5 

259,340 

53 

6 

344,123 

25 

7 

266,233 

42 

6 

331,383 

42 

5 

312,385 

25 

14 


Bulletin  110. 


No  particular  care  or  tricks  of  manipulation  were  used  in  order  to 
seed'bec^un^er  favorable  Yond^ttensttm  percentages  of°seed ^er^hia- 

failed  to  grow. 


No.  of 
Samples 

1 

2 

3 

4 

5 

6 

7 

8 
9 

10 

11 

12 


RESULTS  OF  SPROUTING  EXPERIMENTS— 1906 
Quality  of  Seed 


Age  in 
Years 


Seed  per 
Pound 


Prime  seed  .  1^ 

Prime  seed  .  ^ 

Prime  seed  .  .1^ 

Prime  seed  .  ^ 

Prime  seed  .  1^ 

Prime  seed  . 1® 

Screenings,  first  quality  ...  H 

Screenings,  first  quality  ...  12 

Screenings,  first  quality  ...  13 

Screenings,  second  quality  .  .  12 

Screenings,  third  quality  ...  1 1 

Prime  seed  .  ^ 


206,837 

228,818 

208,821 


Per  Cent. 
Germinating  Average 
(  94 


259,340 

344,123 

266,233 

331,383 

312,385 

288,267 


91 

84 

80 

73 

76 

70 

76 

66 

66 

69 
57 
30 
36 
21 
11 
28 
48 
11 
17 
14 
14 
65 

70 


92.5 
82.0 
74  i  5 
73.0 

66.0 

i 

63.0 

33.0 

16.0 

38.0 

14.0 

14.0 

67.5 


Four  other  experiments  were  made  with  sample  No.  1,  because  I 

eathered  this  seed  myself  in  the  summer  of  1894  and  the  preceding 
tables  sho  w  that  in  12  years  it  has  lost  only  2.5  per  cent  of  its  germinat¬ 
ing  power.  The  results  at  the  end  of  five  days  were  as  follows. 

Seed  Taken  Rotted  Hard  Seeds  Seeds  Sprouted 

100  f  t  94 

100  1  5  qq 

100  1  f  qq 

The  average  of  these  four  experiments  is  94.25  per  cent  which 
is  very  nearly  as  high  as  the  result  obtained  with  this  sample  m  1896 
when  h  was  only  two  years  old.  The  results  obtained  with  this  sarn¬ 
ie  96  per  cent  germinating  when  the  sample  was  two  years  old 

with  «!.«„,  precaution  to  pre- 
VeEtSampfe  N0om6”howT'quite  a  deterioration  in  the  10  years  lapsing 

bampieiNo.os  4  .  .  when  six  years  old  this  sample 

cut,  though  it  hat,  been  hep. 


Alfalfa. 


15 


LI'  b0ti  ®  ln  a  show  ca<se>  exposed  to  a  strong  light  and  to  all 
t  e  changes  of  temperature  for  five  seasons  in  Colorado;  when  ten 
years  old  showed  a  germination  of  72  per  cent  and  when  16  years  old 
a  germmation  of  63  per  cent.  The  conditions  under  which  thTs  sam- 
ple  has  been  preserved,  especially  during  the  first. six  years,  were  less 
t  A  fb  e  fSr  the  Preservation  of  its  vitality  than  would  ordinarily  be 

t  a  e-  S°  1  th'nl? safe  to  conclude  that  the  limit  for  the  vitality 

good,  mature  alfalfa  seed  exceeds  16  years. 

T^e  screenings,  as  will  be  seen  by  referring  to  the  tables,  stand  in 
the  same  relative  order  of  vitality  that  they  did  ten  years  ago.  The 
deterioration,  however,  is  very  marked  for  all  of  them.  The  screen¬ 
ings  jotted  badly  m  1896,  worse  in  1900  and  still  worse  in  1906. 

L-i  •  dl?  eXpf!^®ntS  1896  as  many  as  per  cent  of  them  rotted 
w  i  e  m  those  of  1906  as  high  as .86  per  cent  of  the  same  sample  rotted. 

ave  previously  stated  that  bright,  vigorous  sprouts  were  des¬ 
troyed  by  coming  m  contact  with  the  rotting  seed  and  owing  to  this  fact, 
1  doubt  whether  any  plants  would  have  survived,  had  the  seed  been 
used  for  actual  planting.  I  endeavored  to  prevent  the  rotting  bv 
wetting  the  upper  piece  of  blotting  paper  with  a  solution  of  bichloride 
of  mercury  but  when  I  stopped  the  rotting  I  practically  stopped  the 
sprouting.  My  solution  was  evidently  too  strong.  I  also  made  sepa¬ 
rate  tests  on  samples  No.  7,  8,  9  and  10  by  first  soaking  them  in  pure 
water  for  two  and  a  half  hours  and  then  for  forty  minutes  in  the  bich¬ 
loride  solution ;  this  prevented  the  rotting  but  evidently  injured  the 
seed  as i  the  results  clearly  show,  of  No.  7,  10  per  cent,  of  No.  8, 1  per 
cent  of  No.  9,  4  per  cent  and  of  No.  10,  3  per  cent  sprouted.  Some 
of  these  sprouts  were  not  strong  but  they  were  bright  and  healthy 
looking ,  they  did  not  rot  like  the  others. 

I  call  especial  attention  to  sample  No.  12  in  the  series  of  1906 
because  it  shows  how  different  lots  of  this  seed  may  vary.  This 
sample  was  obtained  in  1905  as  a  sample  of  prime,  fresh  seed,  but  the 
best  of  the  seeds  were  small.  It  required  288,267  of  them  to  make  a 
pound,  whereas,  of  No.  9,  first  class  screenings,  it  required  266,233  seeds 
to  make  a  pound.  Only  42  per  cent  of  No.  12  were  good,  bright 
seed  and  only  10  per  cent  of  the  sample  could  be  classed  as 
good,  bright,  plump  seed,  and  these  10  per  cent  were  smaller,  actu¬ 
ally  weighed  less,  than  the  average  seed  of  sample  No.  1.  The 

Ti,^eLCen^  were  small,  green  or  brown  and  many  of  them  shriveled, 
inis  58  per  cent  would  have  been  removed  by  proper  cleaning.  The 
results  of  the  sprouting  experiments  indicate  this  clearly  for  79  per 
cent  of  No.  9  sprouted  when  the  seed  was  three  years  old  and  only 
67.5  per  cent  of  No.  12  sprouted  when  theseed  was  two  years  old.  I  may 
urt_  er  remark  that  this  sample,  No. 12,  rotted  badly  showing  that  the 

rotting  is  due,  as  previously  suggested,  more  largely  to  the  sample 
than  to  its  age. 


The  Size  and  Length  of  Alfalfa  Roots. — There  is  no  subject  on 

i/\ #reater  variety  of  statements  can  be  found  than  on  this, 
lhe  alfalfa  root  system  as  it  develops  in  our  soil  is  very  simple  as 
shown  by  the  illustrations  in  Bui.  No.  35.  It  consists  of  a  tap  root 


16 


Bulletin  110. 


with  very  few  small  side  roots.  Nothing  in  connection  with  this 
plant  seems  more  marvelous  to  me  than  the  fact  that  the  simp  e, 
root  system  of  this  plant  can  produce  such  a  luxuriant  growth  of  top. 
The  average  root,  even  at  the  crown,  is  less  than  1-2  inch  in  diameter 
but  I  believe  that  the  shortest  normal  root  that  I  have  dug  up  was 
about  6  feet  long  and  the  longest  one  12  1-4  feet.  Their  ability  to 
penetrate  hard  soil  is  very  great,  but  of  course  there  are  instances  m 
which  some  of  the  roots  fail  to  penetrate  hard  layers.  The  average 
reader  will  understand  that  by  hard  soil  I  do  not  mean  rock,  still  1 
have  followed  roots  through  layers  of  such  tenacity  that  a  pick  was 
indispensible  in  removing  the  earth — and  while  the  root  was  some¬ 
times  twisted  and  crooked  it  was  usually  of  good  size  and  always 

healthy.  ,  _  .  ,, 

Anyone  desiring  a  fuller  discussion  of  these  and  many  other 

points  relative  to  alfalfa  will  find  it  in  Bulletin  No.  35,  to  which  I 

have  had  occasion  to  refer  repeatedly. 


Bulletin  in 


May,  1906 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College. 


A  1  fa  1  fa 

(A  SYNOPSIS  OF  BULLETIN  NO.  35) 


- BY - 


WM.  P.  HEADDEN 


> 


4 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
Fort  Collins,  Colorabo. 

1  90ft. 


The  Agricultural  Experiment  Station. 

FORT  COLLINS,  COLORADO 


THE  STATE  BOARD  OF  AGRICULTURE 


Hon.  P.  F.  SHARP,  President . 

Hon.  HARLAN  THOMAS . 

Hon.  JAMES  L.  CHATFIELD . 

Hon.  B.  U.  DYE . . . 

Hon.  B.  F.  ROCKAFELLOW . 

Hon.  EUGENE  H.  GRUBB . 

Hon.  A.  A.  EDWARDS . 

Hon.  R.  W.  CORWIN . 

Governor  JESSE  F.  MCDONALD, 
President  BARTON  O.  AYLESWORTH, 


. .  .Denver . 

_ Denver . 

. . .  Gypsum - 

. . .  Rocky  Ford 
. .  .Canon  City. 

. .  .Carbondale. 

. . .  .Fort  Collins 
. . .  Pueblo . 

|  ex-officio. 


TERM 

EXPIRES 

....1907 
..  .1907 
....1909 
....1909 
....1911 
....1911 
....1913 
....1913 


A.  M.  HAWLEY,  Secretary  EDGAR  AVERY  Treasurer 

Executive  Committee  in  Charge 


P.  F.  SHARP,  Chairman.  B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS 


STATION  STAFF 


L.  G.  CARPENTER,  M.  S.,  Director . Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S . Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D . . . Chemist 

W.  PADDOCK,  M.  S . Horticulturist 

W.  L.  CARLYLE,  M.  S . Agriculturist 

G.  H.  GLOVER,  B.  S.,  D.  V.  M . Veterinarian 

W.  H.  OLIN,  M.  S., . Agronomist 

R.  E.  TRIMBLE,  B.  S . Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S..., . Assistant  Chemist 

EARL  DOUGLASS,  M.  S . Assistant  Chemist 

S.  ARTHUR  JOHNSON,  M.  S . Assistant  Entomologist 

B.  O.  LONGYEAR,  B.  S .  Assistant  Horticulturist 

J.  A.  McLEAN,  A.  B.,  B.  S.  A . Animal  Husbandman 

E.  B.  HOUSE,  B.  S  . ...Assistant  Irrigation  Engineer 


F.  KNORR . Assistant  Agriculturist 

P.  K.  BLINN,  B.  S . Field  Agent,  Arkansas  Valley,  Rocky  Ford 

E.  R.  BENNETT,  B.  S . Potato  Investigations 

Western  Slope  Fruit  Investigations,  Grand  Junction: 

O.  B.  WHIPPLE,  B.  A . Field  Horticulturist 

ESTES  P.  TAYLOR,  B.  S . Field  Entomologist 


OFFICERS 


President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L  G.  CARPENTER,  M.  S . Director 

A.  M.  HAWLEY . Secretary 

MARGARET  MURRAY . Stenographer  and  Clerk 


ALFALFA 


(a  synopsis  of  bulletin  no.  35.) 


By  Wm.  P.  Headden 


Bulletin  No.  35,  issued  in  1896,  is  still  in  constant 
demand.  This  bulletin  consists  of  nearly  100  pages,  and 
covers  a  large  part  of  the  matters  relating  to  this  valuable 
plant.  Because  of  its  size,  however,  and  its  not  being  indexed,  it  is 
difficult  to  find  a  fact  or  statement  to  which  one  may  wish  to  refer. 
Further,  because  of  the  unusually  large  edition  issued,  and  the 
cutting  down  of  the  mailing  list  "made  at  the  same  time,  there- 
a  large  excess,  of  which  a  number  still  remains.  A  synopsis,  such 
as  is  here  given,  will  take  the  place  oFan  index  and  will  be  useful 
both  to  those  who  already  possess  a  copy  of  No.  35  and  to  those 
who  may  in  the  future  receive  one.  This  synopsis  is  therefore 
prepared  as  a  supplement  to  bulletin  No.  35.  Owing  to  its  size 
it  is  not  likely  that  No.  35  will  be  re-issued,  as  bulletin  no,  and 
this  synopsis,  will  fill  its  place,  so  far  as  the  demands  of  the 
general  public  are  concerned. 

Copies  of  the  original  bulletin  may  still  be  obtained  on  ap¬ 
plication. 


4 


THE  COLORADO  EXPERIMENT  STATION 


PAGE 


Object  and  Scope  of  Bulletin 


2 


History  of  Alfalfa 


2-4 


Description  of  the  plant;  native  place,  probably  Media, 
whence  the  name  Medick;  introduced  into  England  1650; 
cultivated  by  Greeks  and  Romans;  culture  has  not  been  con¬ 
tinuous  in  Italy;  brought  to  South  America  by  the  Spanish; 
brought  from  Chili  to  California  in  early  fifties;  1854;  brought 
to  Colorado  in  the  early  sixties,  1862-3(?). 

Culture . 4-8 

Methods  in  vogue  essentially  the  same  as  have  been  in  use 
for  centuries.  Methods  differ  slightly  for  different  soils  and 
climates.  Cold,  wet  winters  and  poor  drainage  constitute  bad 
conditions  for  cultivation  of  this  plant.  It  is  customary  to 
sow  with  a  protective  crop 

Seed. — Screenings  produce  good  stand  of  healthy  plants,  suffi¬ 
cient  to  produce  maximum  crop.  Seed  bed  should  be  deeply 
prepared  and  plants  receive  abundant  water  during  first  sea¬ 
son.  Tap  roots  not  always  present.  Transplanting  has  been 
practiced  with  good  results.  Three  cuttings  made  in  Eng¬ 
land  and  seven  in  Catalonia.  Alfalfa  yields  better  hay  when 
sown  broadcast  than  when  sown  in  drills.  Life  of  the  plant 
is  given  as  from  two  to  fifty  years.  Alfalfa  needs  water  to  pro¬ 
duce  a  crop.  Its  long  roots  may  enable  it  to  live  without  much 
water,  but  not  to  produce  a  good  growth.  Alfalfa  does  well 
in  a  wide  range  of  soils;  also  of  altitude. 


8-9 


Varieties 


Two  varieties,  at  least,  in  alfalfa  as  grown  in  Colorado;  one 
has  red  stem,  small,  dark  green  leaves  and  dark  purple  blos¬ 
soms;  the  other  has  green  stems,  large  and  lighter  green 
leaves,  and  lighter  blossoms.  The  red  stemmed  plants  are 
earlier  and  leafier  than  the  green  stemmed. 

Three  French  varieties  experimented  with  did  not  retain 
their  distinctive  features. 

Turkestan  alfalfa  experimented  with  did  not  change  its 
character. 

There  are  but  slight  differences  in  the  composition  of  the 
varieties. 

Composition  of  Alfalfa,  Hay,  Heaves,  Stems,  etc.  .  .  9-32 

Preparation  of  samples. 

Samples  dried  in  the  air  and  at  100°  show  no  difference  in 
composition.  It  is  not  well  to  dry  above  100°,  page  9. 


ALFALFA 


5 


PAGE 

Samples  taken  before  bloom,  beginning  bloom,  half  bloom, 
full  bloom,  with  seed  formed  and  with  mature  seed. 

Samples  of  flowers,  leaves,  stems,  roots,  etc. 

Proteids  in  Alfalfa  at  Different  Periods  of  Growth  and  in 

Alfalfa  Hays  at  Ditferent  Cuttings . io-ii 

The  average  percentage  of  proteids  found  in  our  laboratory 
samples,  were:  in  first  cutting  alfalfa,  about  14.0  per  cent.; 
in  the  second  cutting,  14.43  per  cent. ;  in  the  third  cutting,  13.05 
percent.  In  the  farm  samples,  first  cutting,  14.92  per  cent.; 
second  cutting,  13.99  per  cent.;  third  cutting,  13.47  per  cent. 

Analysis  of  Alfalfa  Hay  as  Cut  and  of  the  Same  Dam¬ 
aged  by  Rain .  12 

As  cut,  ash,  12.18;  crude  fat,  3.94;  crude  protein,  18.71;  crude 
fibre,  26.46;  nitrogen  free  extract,  38.71.  Damaged  by  rain: 

Ash,  12.71;  crude  fat,  3.81;  crude  protein,  11.01;  crude  fibre, 

38.83;  nitrogen  free  extract,  33.64. 

First  cutting  hay  contains  more  proteids  than  second  or  third 
cutting. 

Amount  of  proteids  is  nearly  stationary  from  beginning  to 
half  bloom,  and  decreases  after  full  bloom. 

Crude  Fibre . 13-16 

Percentage  of  crude  fibre  varies  a  little,  due  to  varieties ;  also 
to  conditions  of  soil  and  moisture. 

Percentage  of  crude  fibre  increases  with  age  of  plant,  but  is 
fairly  constant  from  the  period  of  early  to  full  bloom. 

Peroentage  of  crude  fibre  in  supposedly  distinct  varieties 
grown  in  drills  was  the  same  as  in  ordinary  hays. 

Percentage  of  crude  fibre  in  second  cutting  hay  is  essentially 
the  same  as  in  the  first  cutting. 

The  percentage  in  third  cutting  varies  more  than  in  the  others, 
but  averages  about  the  same. 

Fat  or  Ethei  Extract . 16-17 

The  average  percentage  extracted  is  1.539  per  cent. 

Nitrogen  Free  Extract . I7_I9 

Average~percentages  obtained  from  labratory  samples  were: 

For  first  cutting  hay . 31.69 

For  second  cutting  hay . 34.27 

For  third  cutting  hay . ,32.72 

Average  percentages  obtained  from  field  samples  were: 

For  first  cutting  hay . 34.35 

For  second  cutting  hay . 34.04 

For  third  cutting  hay . 34.74 


6 


THE  COLORADO  EXPERIMENT  STATION 


PAGE 

Moisture  in  Air  Dried  Hay . .  •  x8 

The  moisture  in  the  laboratory  samples  averaged  6.03  per 
cent,  the  field  sample,  7.09  per  cent.;  under  ordinary  Colo¬ 
rado  conditions  the  average  will  not  be  far  from  6.5  per  cent. 

Air  dry  alfalfa  hay  under  our  usual  conditions  absorbs  moist- 
ture  rapidly.  One  ton  of  ordinary  air  dry  hay  will  readily  ab¬ 
sorb  llTpounds  of  moisture  during  a  damp  spell. 

Ash  or  Mineral  Constituents . 19-21 

The  amount  of  ash  present  in  alfalfa  hay  varies  but  slightly. 

The  average  for  the  first  cutting  is  9.08  per  cent.;  for  second 
cutting  10.24,  and  for  the  third  cutting  9.83  per  cent,  for  our 
laboratory  samples..  The  results  for  the  field  samples  were  a 
little  higher,  11.19,  10.48,  and  10.07  per  cent,  for  the  respective 
cuttings.  These  figures  are  for  the  pure  ash.  A  five-ton  crop 
of  alfalfa  removes  about  1,025  pounds  of  ash  or  mineral 
matter. 

Water  in  Alfalfa . 21-22 

The  average  percentages  of  water  in  the  first  and  second 
cuttings  are  73.14  and  71.08.  The  water  in  the  third  cutting 
was  not  determined.  Other  determinations  for  the  first  and 
second  cutting  gave  74.76  per  cent,  for  the  former,  and  72.80 
per  cent,  for  the  latter.  One  hundred  pounds  of  green  alfalfa, 
first  cutting,  makes  about  27  pounds  of  hay;  and  100  pounds 

of  second  cutting  makes  about  29  pounds  of  hay. 

» 

Amids ,  Amid  Nitrogen . 22-25 

The  amid  nitrogen  in  the  first  cutting  of  alfalfa  hay  corre¬ 
sponds  to  10.85  per  cent,  of  the  total  crude  proteids  or  albu¬ 
minoids,  and  19.93  per  cent,  of  the  total  in  the  second  cutting, 
while  we  found  but  5.03  per  cent  for  the  third  cutting. 

Colorado  samples  differ  greatly  from  Texas  samples  given  in 
Texas  Bulletin  No.  20,  1892. 

The  amids  probably  reach  their  maximum  at  about  the  period 
of  half  bloom,  as  they  begin  to  disappear  as  the  plants  go  out 
of  bloom. 

The  bloom  itself  is  rich  in  amids  (see  p.  28  for  analysis). 


About  20.28  per  cent,  of  the  total  albuminoids  being  amids. 

Nitrogen  as  Nitric  Acid .  25 

Nitrogen  is  not  present  in  this  form — the  result  of  18  tests. 

Parts  of  the  Plant . 25-32 


Stems  p .  25. — Average  diameter,  0.17  of  an  inch;  height  five  and 
one-half  feet  under  favorable  conditions.  Proportion  from  40 
to  60  per  cent,  of  the  plant;  the  rest  of  the  plant  is  represented 


ALFALFA 


7 


PAGE 

essentially  by  the  leaves.  The  fresh  stems  contain  about  60 
per  cent,  of  their  weight  of  water.  The  mechanical  loss  in 
making  alfalfa  hay  is  from  15  to  20  and  even  66  per  cent. 
Composition  of  alfalfa  stems  is  that  of  a  fairly  good  hay,  p.  26. 

The  amid  nitrogen  in  the  stems  is  very  low. 

Leaves,  p.  27. — Alfalfa  leaves  affected  by  a  fungus,  p.  27.  Fresh 
leaves  contain  68.72  per  cent,  of  water.  The  leaves  are  very 
rich  in  proteids  up  to  half  bloom,  but  are  not  so  rich  when 
past  full  bloom. 

The  amids  in  the  leaves  are  high,  about  15.65  per  cent,  of  the 
total  albuminoids. 

The  percentage  of  ash  in  the  leaves  is  high,  about  14.00  per 
cent. 

A  large  percentage  of  the  leaves  is  lost  in  hay  making,  (p.  26). 
Flowers,  p.  28.—  The  flowers  are  important  as  they  indicate  the 
turning  point  in  the  development  of  the  plant.  The  fresh 
flowers  contain  72.69  per  cent,  of  water.  The  composition  of 
the  flowers  is  similar  to  that  of  the  leaves. 

Analyses  p.  28.— The  amids  are  more  abundant  in  the  flowers 
than  in  any  other  portion  of  the  plant.  The  flowers  are  not 
sufficiently  abundant  to  account  for  the  large  amount  of  pro¬ 
teids  in  the  hay  cut  when  the  plants  are  in  half  bloom.  The 
ether  extract  of  the  flowers  is  not  very  high  and  does  not 
foreshadow  the  large  amount  of  oil  in  the  seed. 

Review  of  Questions  Relating  to  Alfalfa  Hay  Mak¬ 
ing  . 29-32 

The  time  of  cutting;  the  influence  of  irrigation;  the  influence 
of  growing  on  high  and  low  lands;  comparison  of  results  ob¬ 
tained  in  Texas,  New  Jersey,  and  Colorado.  The  composition 
of  the  various  cuttings  shows  but  little  variation. 

Composition  is  not  the  only  factor  in  making  a  good  hay. 

Analyses  of  alfalfa  hays,  laboratory  samples,  made  from 
plants  at  different  periods  of  development,  grown  without  irri¬ 
gation,  on  low  land  and  on  high  land,  p.  31. 

Analyses  of  parts  of  the  plant  grown  under  same  variety  of 
conditions,  p.  31. 

Analyses  of  alfalfa  hays,  farm  samples,  p.  32. 

Alfalfa  and  Clover  Hay  Compared . 32-33 

Analyses  of  clover  and  alfalfa  hays,  p.  32.  Green  alfalfa 
yields  2.5  per  cent,  more  hay  and  contains  about  7.00  per  cent, 
more  digestible  food  than  clover. 

Alfalfa,  Red  Clover  and  Pea  Vine  Ensilage  Com¬ 
pared  . .  .  .  .  33-34 

•  The  dry  matter  in  alfalfa  ensilage  is  30.19  per  cent.  Analyses 


8 


THE  COLORADO  EXPERIMENT  STATION 


PAGE 

of  alfalfa,  pea  vine  and  clover  ensilages,  p.  33.  The  pea  vine 
ensilage  was  made  from  pea  vines  after  the  peas  had  been 
threshed  out  for  canning  purposes.  The  ash  in  alfalfa  ensil¬ 
age  is  much  higher  than  in  the  hay,  indicating  a  considerable 
loss  of  dry  matter. 

Alfalfa  ensilage  is  eaten  freely  by  cattle.  The  so-called 
“brown  hay”  is  alfalfa  hay  which  has  passed  through  a  fer¬ 
mentation  in  the  stack  and  is  considered  an  excellent  fodder 
for  cattle.  Alfalfa  ensilage  is  easily  damaged  by  putrefactive 
fermentation. 

Analysis  of  damaged  alfalfa  ensilage,  p.  34. 

Plant  Food  taken  from  the  Soil  by  Alfalfa  ....  35-37 

Leguminous  plants  such  as  alfalfa  are  considered  as  nitrogen 
gatherers,  and  when  they  are  incorporated  with  the  soil  in 
which  they  have  grown  add  nitrogen  to  it,  but  when  they  are 
removed  it  is  questionable  whether  this  is  so  or  not. 

The  ash  content  obtained  from  our  samples  probably  repre¬ 
sents  the  normal  amount  which  a  healthy  alfalfa  plant  will 
take  up. 

Table  showing  the  pounds  of  the  various  plant  foods  removed 
by  1,000  pounds  of  alfalfa  hay.  One  ton  first  cutting  alfalfa 
hay  removes  143  pounds  of  ash  constituents;  one  of  second 
cutting.,  165  pounds,  and  one  of  third  cutting,  127  pounds. 
Carbon,  carbonic  acid,  and  sand  not  reckoned.  One  ton  clo¬ 
ver  hay  removes  128  pounds  of  ash  constituents. 

Alfalfa  Seeds . 37-44 

Analysis  of  seeds,  p.  31;  analysis  of  ash,  p.  92.  Description 
and  size  of  alfalfa  seed,  prime  seed,  1st,  2d  and  3d  quality  of 

screenings,  p.  38.  Amount  of  seed  sown  to  the  acre,  p.  39. 

•  .  « 

What  Constitutes  a  Good  Stand  of  Alfalfa  ....  39-40 

Hay  produced  by  single  plants  in  thick  and  light  stands. 
Number  of  stems  thrown  up  by  individual  plants,  p.  41.  Stems 
produced  by  plants  having  much  space  are  not  larger  than 
those  produced  by  plants  which  are  crowded;  the  size  of  the 
stems  is  influenced  by  other  conditions.  The  amount  of  seed 
necessary  to  produce  a  good  stand  depends  upon  the  vitality 
of  the  seed  and  the  vigor  of  the  plants  produced. 

Vitality  of  Alfalfa  Seed . 4I_44 

Alfalfa  seed  said  to  be  low  in  vitality.  Experiments  made  to 
refute  this  statement.  Description  of  samples  of  seeds  used. 

How  the  experiment  were  made.  Results  of  experiments  p. 

43.  “Hard  Seed”  explained  and  germinating  power  given, 
p.  43.  Duration  of  experiment,  three  days,  sufficient  to  form 


ALFALFA 


9 


PAGE 

a  judgment  of  the  value  of  the  seed.  Six-year-old  alfalfa 
seed  had  lost  but  little  or  none  of  its  germinating  power. 
Screenings  give  good  results  even  when  two  or  three  years 
old.  Failures  to  obtain  a  stand  are  due  to  causes  other  than 
the  lack  of  germinating  power  of  the  seed. 

Roots  and  Stubble  of  Alfalfa . 44-64 

The  popular  description  of  the  roots  exaggerated  and  errone¬ 
ous.  Very  large  roots  exceptional  and  not  normal.  The 
root  system  is  very  simple,  Plates  II  to  X.  Fibrous  roots 
are  almost  wanting.  Spongioles  found  at  the  depth  attained 
by  the  tap  roots.  Spongioles  described. 

Depth  Attained  by  the  Roots. 

The  depth  attained  by  alfalfa  roots  varies  with  fehe  soil;  it 
may  also  be  determined  by  the  height  of  the  water  plane. 
Alfalfa  roots  are  more  tolerant  of  water  than  popularly  sup¬ 
posed.  Illustrated  in  Plate  XIII. 

Locality  in  Weld  County  chosen  for  digging  out  samples  of 
alfalfa  roots,  p.  48.  Section  of  soil  given,  p.  48.  Plants  were 
five  or  six  years  old  and  vigorous.  Roots  had  penetrated  the 
hard  layer  and  did  not  divide.  Depth  reached  was  eleven  feet 
nine  inches,  ending  in  a  soft  sandy  clay.  At  the  next  place 
chosen  the  soil  was  nearly  uniform  to  depth  attained  by  roots. 

This  soil  was  a  clay  and  was  formerly  used  for  making  brick. 

Age  of  these  plants  five  or  six  years;  length  of  roots  twelve 
feet  three  inches.  Effect  of  raising  the  water  plane,  p.  49. 


Effect  of  Age  on  Size  of  Roots .  50 

Observations  show  great  variation;  some  nine  months  old 
roots  are  larger  than  others  six  years  old. 

Death  Rate  of  Roots . 50 


In  five  years  from  seeding  two-thirds  of  the  plants  had  died. 

.  The  yield  of  hay  not  affected.  Dying  out  of  the  plants  or  thin¬ 
ning  of  the  stand  not  objectionable  provided  it  is  uniform. 

The  plants  die  in  two  ways,  p.  51.  The  second  mode  of  dying 
illustrated  by  plates  XV,  XVI  and  XVII.  Alfalfa  roots  when 
cut  off  below  the  crown  do  not  bud  and  reestablish  the  plant, 
and  their  power  of  throwing  out  adventitious  roots  is  small. 

Alfalfa  Roots  Cut  by  Gophers . •  .  .  .  .  52 

Alfalfa  plants  endure  this  root  pruning  to  a  remarkable 
extent. 

Nodules  on  Alfalfa  Roots . 52'53 

These  occur  in  three  forms;  as  warty  excrescences  on  the 
roots,  in  large  colonies,  and  as  single  nodules.  The  first 


IO 


THE  COLORADO  EXPERIMENT  STATION 


PAGE 

form  occurs  near  the  surface;  the  second  is  most  abundant 
at  depths  of  from  three  to  five  feet;  and  the  third  at  all  depths 
up  to  eleven  and  a  half  feet.  Illustrated  in  Plates  XI.  and 
XIV.;  also  shown  in  Plate  XIII.  Partial  analysis  of  nodules 
page  53. 

Ratio  of  Roots  to  the  Tops . 53-54 

This  ratio  varies  greatly  with  individual  plants.  In  field 
culture  it  is  more  than  an  average  alfalfa  plant  on  which  the 
top  equals  or  exceeds  the  weight  of  the  root. 

Alfalfa  Stubble .  55 

The  stubble,  taken  to  a  depth  of  six  inches,  five  days  after 
cutting,  is  equal  to  about  two  thirds  of  the  weight  of  the  green 
alfalfa  as  cut  by  the  mower.  The  dried  stubble  found  per 


acre  ranging  from  2.5  to  3.34  tons. 

Composition  of  the  Stubble .  56 

Analysis  of  ash  of  stubble,  page  92. 

Mineral  constituents  per  1,000  pounds  of  stubble,  page  56. 

Composition  op  the  Roots . 56-58 

Analyses  of  ash  of  roots,  bark,  and  inner  portion,  page  92. 


Methods  of  preparing  roots— could  not  wash  them,  page  56. 

Fresh  roots  contain  60.41  per  cent,  water.  Fodder  analyses 
of  root,  page  57.  Ash  constituents  are  easily  washed  out  of 
the  roots.  Properties  of  aqueous  extract  of  roots,  page  57. 

The  presence  of  starch  doubtful.  Mineral  plant  food  con¬ 
tained  in  each  1,000  pounds  of  air  dried  roots,  page  58.  Ash 
constituents  dissolved  out  of  roots  by  water  equal  11.99  pounds 
per  thousand.  Phosphoric  and  sulphuric  acids,  but  particu¬ 
larly  potash,  went  into  solution. 

Manurial  Value  of  Stubble .  59 

Each  ton  of  stubble  contains  8.31  pounds  of  phosphoric  acid, 

15.52  pounds  of  potash.  36.37  pounds  of  nitrogen;  giving  the 
value  of  the  stubble  at  $6.75 per  ton,  or  $19.28  per  acre. 

Manurial  Value  of  the  Roots .  60 

The  weight  of  roots  per  acre  is  nearly  twice  as  great  as  that 
of  the  stubble,  but  is  not  so  rich  in  phosphoric  acid  and 
nitrogen;  the  manurial  value  of  the  roots  per  acre  is  about 
$16.  58.  Without  assigning  any  value  to  the  organic  matter 
we  have  $35.90  as  the  value  of  the  alfalfa  stubble  and  roots. 

This  food  is  within  the  reach  of  ordinary  plants;  wheat  for 
example.  If  the  alfalfa  roots  were  removed,  the  soil  would 
be  found  poorer  than  before  the  alfalfa  was  grown  on  it,  es¬ 
pecially  in  nitrogen,  the  first  nine  inches  of  soil  excepted, 
page  61. 


ALFALFA 


II 


PAGE 

The  Leaves  and  Stems  as  a  Top  Dressing . 61-63 

The  leaves  and  stems  which  fall  on  the  ground  to  become  in¬ 
corporated  with  it  amount  to  about  one  ton  a  year,  which 
accounts  for  the  fact  that  the  first  nine  inches  of  soil  in  which 
alfalfa  had  been  grown  was  found  to  contain  more  than  half 
the  nitrogen  contained  in  the  soil  to  a  depth  of  nine  feet,  8.9 
pounds  out  of  17.0  pounds  in  all.  There  is  an  accumulation 
of  plant  food  in  the  upper  portions  of  the  soil  which  is  of 
material  benefit.  Elements  of  plant  food  contained  in  1,000 
pounds  of  leaves,  page  36.  Fodder  analyses  of  leaves,  p  27. 
Analyses  of  ash  of  leaves,  p.  92.  Fodder  analyses  of  stubble  and 
roots  of  alfalfa,  p.  63.  Analyses  of  ashes  of  stubble  and 
roots,  page  92.  Elements  of  plant  food  in  1,000  pounds  of 
stubble  and  roots,  page  63. 

The  Soil  and  Its  Relation  to  Alfalfa  Growing  .  .  .  63-77 

Weld  county  soil  described,  page  63-64.  Ash  constituents  and 
nitrogen  removed  by  1,000  pounds  of  hay  grown  on  this  soil, 
page  64.  Analyses  of  the  ashes  of  the  plants  and  roots  of 
alfalfa  grown  on  the  soil.  Chemical  analyses  of  the  five 
sections  of  this  soil,  page  65.  The  mechanical  analyses  of 
this  soil,  page  66.  Physical  condition  of  soil  is  good,  and 
from  a  chemical  standpoint  the  supply  of  phosphoric  acid, 
potash  and  nitrogen  is  abundant.  The  total  mineral  con¬ 
stituents  removed  by  a  four  and  a  half  ton  crop  of  alfalfa 
hay  from  this  soil  is  677.88  pounds;  carbon  dioxide  not  in¬ 
cluded.  Respective  amounts  of  the  several  constitutents, 
page  67.  The  nitrogen  in  the  hay  amounts  to  200.79  pounds. 
Though  the  plant  food  in  this  soil  is  very  abundant  the  ash 
content  of  the  hay  is  about  the  average.  Similar  data  rela¬ 
tive  to  Otero  county  soil,  page  68.  Analysis  of  Otero  county 
soil,  page  69.  The  plant  food  removed  by  the  hays  grown  on 
these  two  soils  bears  no  relation  to  the  relative  quantities 
shown  by  their  chemical  analyses.  The  ground  water  seems 
to  have  but  little  or  no  influence  upon  mineral  matters  taken 
up.  Magnesia  studied  as  a  criterion.  Composition  of 
ground  water  encountered  in  Otero  county  soil,  page  70.  The 
sum  of  the  lime  and  potash-magnesia  included  with  the  former 
and  soda  with  the  latter — is  constant  within  narrow  limits 
and  suggests  a  partial  interchange  of  functions,  page  71. 

The  magnesia  and  soda  in  the  ash  of  the  Otero  county  hay 
was  not  affected  by  the  magnesia  and  soda  in  the  ground 
water.  Ashes  of  hays  grown  in  alkali  soils  in  Larimer  county 
contained  two  or  three  times  as  much  soda  as  the  Weldor 
Otero  county  samples. 

Otero  County  Ground  Water  and  Larimer  County 

Seepage  Water  Stated  in  Grains  Per  Gallon.  72 

The  ground  and  seepage  waters  differ  wholly  from  the  river 
waters  used  in  irrigation.  These  waters  do  not  sustain  ihe 
same  relation  to  plant  feeding  that  solutions  do  in  water  cul¬ 
tures.  Analyses  of  ashes  of  the  Weld  county  and  Otero 
county  hays  given  for  comparison,  page  74. 


12 


THE  COLORADO  EXPERIMENT  STATION 


PAGE 

Effects  of  Alfalfa  Growing  on  the  Soils  Restated  74-77 


78-89 


Appendix 


Preparation  of  samples,  page  78.  Preparation  of  ash,  page 
79.  Methods  of  analyses,  pages  80-82.  Determination  of 
phosphoric  acid,  manganese,  lime  and  magnesia,  page  82. 
Determination  of  chlorine  and  sulphur,  page  83.  Loss  of 
chlorin  on  incineration,  page  85.  Maximum,  2.38  per  cent. 
Loss  of  sulphur  on  incineration,  2.0  per  cent.,  page  87.  Loss 
of  phosphorous  or  phosphoric  acid  none,  page  87.  Some 
results  obtained  at  other  stations,  page  89. 

Analyses  of  Colorado  Alfalfa  Hays  and  Parts  of 


Plants 


90 


Analyses  of  hays,  etc.,  pages  31  and  32.  Same  calculated  on 
water  free  basis,  page  90.  Analyses  of  good  alfalfa  hay,  first 
cutting,  moisture,  6.04  per  cent.;  ash  9.30;  fat,  1.19;  crude 
protein,  14.41:  crude  fiber,  36.54;  nitrogen  free  extract,  32.50; 
amid  nitrogen,  0.372  per  cent,  second  cutting,  moisture,  6.61; 
ash,  9.91;  fat,  1.18;  crude  protein,  16.11;  crude  fiber,  37.24; 
nitrogen,  free  extract,  28.90;  amid  nitrogen,  0.350  per  cent. ; 
third  cutting,  moisture,  5.78;  ash,  9.38;  fat,  1.61;  crude  protein 
12  53;  crude  fiber,  39.35;  nitrogen  free  extract,  31.35;  amid 
nitrogen,  0.10  per  cent. 

Compilation  of  Analyses  Published  Prior  to  1896  .  .  91 

Ash  Analyses — All  Colorado  Samples .  92 

Description  of  Plates . 94-95 

Plate  /.—The  largest  individual  plant  found  in  Colorado.  Diam¬ 
eter  of  top.  18  inches,  stems  360. 

Plate  //.—Exhibits  face  of  opening  thirteen  feet  deep  in  alfalfa 
field  on  Experiment  Station  farm  at  Rocky  Ford,  showing 
root  system  and  distribution  in  soil. 

Plates  III .  and  IV . — Largest  roots  dug  out,  11  feet  nine  inches 
long. 

Plates  V.  and  VI.- Show  typical  root  system  of  alfalfa  as  it  grows 
in  Colorado. 

Plates  VII.  and  VIII.—  Show  alfalfa  roots  which  have  branched 
to  a  very  unusual  degree. 

Plate  AT. —Yearling  alfalfa  plants  grown  in  rich  soil.  Three 
feet  nine  inches . 

Plate  X.  —Alfalfa  seedlings  nine  months  old;  roots  nine  feet 
three  and  three-fourths  inches  long. 

Plate  XI.  — Shows  lower  end  of  tap  root  nine  feet  eleven  inches 
long.  Shows  tubercles  at  this  depth. 

Plate  XIII. — Shows  mass  of  fibrous  roots  taken  from  gravel 
filled  with  water. 

Plate  XIV  —  Shows  large  clusters- of  tubercles  234  inches  across 
as  they  were  found  at  a  depth  of  from  three  to  five  feet. 

Plates  XV. , XVI.  and  XVII.—  Show  the  progressive  decay  of  the 
crown  of  the  alfalfa  plant. 

Plate  XVIII.— Shows  gopher  eaten  roots  with  the  small  ad¬ 
ventitious  roots  thrown  out  by  the  alfalfa  plant. 


Bulletin  112 


April,  1906 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College. 


A 

Hopperdozrer 


- BY - 


P.  K.  BLINN 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
Fort  Collins,  Colorado. 

190A 


The  Agricultural  Experiment  Station. 

FORT  COLLINS,  COLORADO 


THE  STATE  BOARD  OF  AGRICULTURE 


Hon.  P.  F.  SHARP,  President  . 

Hon.  HARLAN  THOMAS . 

Hon.  JAMES  L.  CHATFIELD . 

Hon.  B.  IJ.  DYE . 

Hon.  B.  F.  ROCKAFELLOW  . 

Hon.  EUGENE  H.  GRUBB  . 

Hon.  A.  A.  EDWARDS . 

Hon.  R.  W.  CORWIN . 

Governor  JESSE  F.  MCDONALD, 
President  BARTON  O.  AYLESWORTH, 


.  Denver . 

.  .Denver . 

. .  Gypsum  — 

. . Rocky  Ford. 
.  .Canon  City. 

.  .Carbondale. 

. .  Fort  Collins 
. .  Pueblo . 

ex-officio. 


TERM 

EXPIRES 

...1907 
..  .1907 
....1909 
...  1909 
....1911 
....1911 
...1913 
....1913 


A.  M.  HAWLEY,  Secretary 


EDGAR  AVERY  Treasurer 


Executive  Committee  in  Charge 

P.  F.  SHARP,  Chairman.  B.  F.  ROCKAFELLOW.  A  A.  EDWARDS 


STATION  STAFF 

L.  G.  CARPENTER,  M.  S.,  Director . Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S . Entomologist 

W.  P.  HEADDEN,  A.  M.  Ph.  D  . . Chemist 

W.  PADDOCK,  M.  S .  . Horticulturist 

W.  L.  CARLYLE,  M.  S . Agriculturist 

G.  H.  GLOVER,  B  S.,  D.  V.  M . Veterinarian 

W.  H.  OLIN,  M.  S., . .  . Agronomist 

R.  E.  TRIMBLE,  B.  S . Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S . Assistant  Chemist 

EARL  DOUGLASS,  M.  S . Assistant  Chemist 

S.  ARTHUR  JOHNSON,  M.  S . Assistant  Entomologist 

B.  O.  LONGYEAR,  B.  S .  Assistant  Horticulturist 

J.  A.  McLEAN,  A.  B.,  B.  S.  A . Animal  Husbandman 

E.  B.  HOUSE,  B.  S  . Assistant  Irrigation  Engineer 

F.  KNORR .  ...  Assistant  Agriculturist 

P.  K.  BLINN,  B.  S . Field  Agent,  Arkansas  Valley,  Rocky  Ford 

Western  Slope  Fruit  Investigations,  Grand  Junction: 

O.  B.  WHIPPLE,  B.  A . Field  Horticulturist 

ESTES  P.  TAYLOR,  B.  S . Field  Entomologist 


OFFICERS 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S .  Director 

A.  M.  HAWLEY . Secretary 

MARGARET  MURRAY . Stenographer  and  Clerk 


A  HOPPERDOZER 


By  P.  K.  Bunn 


Our  native  grasshoppers  have  been  a  common  pest  in  the  alfalfa 
fields  for  many  years,  principally  infesting  the  edges  of  the  fields, 
along  side  of  dry  ditch  banks,  fences,  or  other  dry  land,  such 
locations  affording  their  favorite  breeding  places.  For  several 
years  it  seems  that  the  “hoppers”  have  been  rapidly  increasing. 
Their  injuries  to  the  hay  crops,  alfalfa  seed  and  honey  yield  of  the 
state  amount  each  year  to  many  thousands  of  dollars,  beside  the 
serious  injuries  to  beets,  beans,  potatoes,  cantaloupes  and  most 
other  crops  that  may  be  growing  adjacent  to  the  field  of  alfalfa  to 
which  they  are  attracted  each  time  after  the  hay  is  cut. 

The  extent  of  their  injuries  the  past  season  was  unusually 
severe  and  quite  general  over  the  state.  In  the  Arkansas  Valley 
the  alfalfa  was  almost  stripped  to  stems  in  many  fields,  and  the 
destruction  of  the  bloom  was  so  complete  as  to  practically  destroy 
the  alfalfa  seed  crop  east  of  Pueblo.  The  loss  of  the  bloom  also 
cut  off  the  honey  crop  from  one  of  the  choicest  honey  producing 
sections  of  the  United  States,  many  of  the  apiarists  being  com¬ 
pelled  to  feed  their  bees  during  the  summer  months.  Serious  in¬ 
juries  were  also  made  on  nearly  all  other  crops  by  the  grasshoppers 
from  the  alfalfa  fields.  The  farmers  resorted  to  spraying,  driving 
and  poisonous  baits,  as  well  as  other  precautionary  measures,  but 
with  only  meagre  results. 

Having  observed  the  shifting  movements  of  the  grasshoppers 
when  the  alfalfa  is  cut,  it  seemed  evident  that  such  a  time  offered 
a  favorable  opportunity  to  destroy  the  pest.  It  seemed  that  a 
hopperdozer  could  be  used  effectively  behind  the  mower;  accord¬ 
ingly  a  dozer  was  constructed  on  rather  an  inexpensive  plan,  one 
which  any  farmer  with  ordinary  tools  could  make  without  the  aid 
of  a  skilled  mechanic. 

The  bottom  of  the  pan  was  a  sheet  of  No.  24  galvanized  iron 
30x96  inches,  the  size  of  sheets  usually  carried  by  hardware  dealers. 


4 


THE  COLORADO  EXPERIMENT  STATION 


This  bottom  was  nailed  with  common  six-penny  nails  to  a  frame 
made  of  two-by-fonrs  that  was  24x96  inches  in  size  and  being  the 
same  in  length  as  the  sheet  of  iron,  but  about  six  inches  nar¬ 
rower,  which  allowed  about  three  inches  to  be  turned  np  and 
nailed  to  the  outside  of  the  frame  on  each  side.  This  made  the 
pan  more  secure.  To  prevent  leakage  a  strip  of  tow  candle  wick- 
ing  was  nailed  beneath  the  iron  between  two  rows  of  nails. 


A  coat  of  paint  completed  a  water  tight  pan  24  inches  wide  in¬ 
side  by  eight  feet  long.  To  the  ends  of  this  pan  were  bolted  sled 
runners  four  feet  long,  cut  from  a  piece  of  2x10.  The  runners 
were  so  placed  as  to  carry  the  pan  about  four  inches  above  the 
ground.  Fig.  1  shows  the  general  plan  of  the  pan  with  the 
runners  attached,  also  four  small  10  inch  cast  wheels  bolted  near 
the  ends  of  the  runners,  also  the  dimensions  as  indicated.  The 
wheels  support  the  runners  only  one  and  a  half  inches  and  steady 
the  pan  over  rough  places.  They  lightened  the  draft  and  allowed 
the  pan  to  be  drawn  over  the  hay  without  catching  and  dragging 
it.  By  hitching  a  horse  in  front  of  one  runner  with  a  short  rope 
and  with  a  longer  rope  from  the  other  runner  hitched  into  the 
hame  staple  of  the  harness,  the  wheels  will  carry  the  dozer  at  right 
angles  and  entirely  to  the  side  of  the  horse,  thus  preventing  the 
hoppers  from  being  frightened  away  from  in  front  of  the  advanc¬ 
ing  pan.  At  the  back  of  the  pan  is  a  light  frame  three  feet  high 
secured  by  uprights  that  are  braced  in  front  to  the  runners.  Over 
this  frame  is  stretched  a  sheet  of  white  table  oilcloth  with  the 
smooth  side  to  the  front.  Every  grasshopper  that  hits  the 
smooth  surface  of  the  oil  cloth  screen  falls  into  the  pan  which  is 
filled  with  about  two  inches  of  water  and  about  a  pint  of  kerosene 
oil  on  the  surface.  The  lower  edge  of  the  oilcloth  is  nailed  with 
strips  to  the  inside  of  the  pan  at  the  back  to  prevent  slopping. 

Plate  I.  shows  the  hopperdozer  complete  ready  to  hitch  to 
and  also  views  of  it  when  in  use  and  the  manner  of  hitching. 


A  HOPPERDOZER 


5 


CDS 

N 

®*5 


£  M 

o.2 
S  Ef 

—  w 

bt  £ 
E  O) 

Je> 

O  *h 

03  oi 
O  0) 


6 


THE  COLORADO  EXPERIMENT  STATION 


The  material  and  its  cost  to  build  the  dozer  at  Rocky  Ford 
was  as  follows: 


One  sheet  of  No.  24  gal vanized  iron,  23  lbs.  at  9  cts - $2.07 


“  “  “  2x4,  8  ft. 

“  “  “  2x10,  8  ft. 

“  “  “1x4,  16  ft. 

Total  _ 32  ft.  at  21  cents _  97)C 

3  yards  of  table  oilcloth  at  18  cents - -  54c 

4  cast  wheels _ _  _ _  ---  50° 

Bolts,  nails  and  rope.  _ _ _ _ _ _  40c 

1  bill  candle  wicking _ _ _ _  jlOc 

Total  cost _  $4.56 


The  hopperdozer  was  first  tried  on  Mr.  J.  R.  Roth’s  six  acres 
of  alfalfa  east  of  Rocky  Ford,  the  field  being  so  infested  that  in 
the  evening  when  the  hoppers  climbed  to  the  top  of  alfalfa  stems 
they  gave  a  yellow  cast  to  the  otherwise  green  field.  They  had 
completely  destroyed  the  alfalfa  bloom  and  the  adjoining  fields  of 
potatoes  and  beets,  and  cantalopes  were  threatened  as  soon  as  the 
alfalfa  should  be  cut.  After  getting  a  start  of  several  swaths  with 
the  mower,  the  dozer  was  started.  The  first  round  with 
the  dozer  the  horse  walked  outside  of  the  alfalfa  while 
the  dozer  covered  the  first  two  swaths  of  the  mower. 
The  movements  of  the  horse  frightened  the  hoppers  from 
the  edge  of  the  field  into  the  pan  or  farther  into  the  field  to 
be  caught  at  some  succeeding  round  with  the  dozer.  In  the  first 
two  rounds,  a  half  bushel  measure  of  grasshoppers  was  skimmed 
from  the  pan;  more  water  and  oil  were  added,  and  the  work  con¬ 
tinued  to  the  center  of  the  field,  catching  the  hoppers  more  rapidly 
at  each  succeeding  round.  The  last  two  swaths  were  so  covered 
with  hoppers  that  the  mower  was  stopped  and  the  dozer  driven 
over  this  standing  strip  with  the  horse  on  a  trot.  The  strip  was 
about  eight  feet  wide  by  seven  hundred  long,  and  once  over  and 
back  on  this  strip,  caught  three  heaping  half  bushels  of  grass¬ 
hoppers.  Many  of  the  hoppers  were  down  in  the  hay  and  after 
about  fifteen  minutes  they  had  crawled  to  the  top,  and  covered  the 
strip  again,  and  again  the  drive  was  made  and  two  half  bushels 
was  the  result. 

The  strip  was  left  standing  for  several  days  and  the  dozer 
run  over  it  several  times  each  day  catching  many  of  the  hoppers 
that  remained  on  the  field. 

The  dozer  was  run  over  the  field  several  times  the  day  it  was 
mowed  and  between  nine  and  ten  bushels  of  grasshoppers  were 
caught  besides  many  that  got  out  of  the  pan  but  died  from  the  effect 
of  the  oil  bath.  A  careful  count  of  the  number  of  grasshoppers 


A  HOPPERDOZER 


7 


in  a  given  measure  was  made  and  it  indicated  that  over  thirty 
thousand  grasshoppers  were  killed  in  each  bushel  caught.  A 
large  part  of  them  were  very  small  hoppers  and  only  a  few,  at 
that  time,  July  nth,  had  developed  wings.  Many  alfalfa  worms 
were  caught  when  the  dozer  was  run  over  standing  alfalfa.  The 
field  has  since  been  comparatively  free  from  hoppers  and  no  ap¬ 
parent  injury  was  made  on  the  adjoining  crops. 

About  ten  days  later  the  dozer  was  used  on  the  field  of  Mr. 
J.  B.  BAyan.  The  hoppers  had  then  developed  wings  so  that  many 
were  able  to  fly  too  far,  thus  preventing  a  very  successful  catch, 
although  several  bushels  of  grasshoppers  were  killed  on  about  two 
acres  of  alfalfa.  Other  farmers  used  the  dozer  and  several  other 
dozers  of  similar  construction  were  built  and  used  in  the  vicin¬ 
ity  of  Rocky  Ford.  In  fields  where  the  grasshoppers  were  unusually 
numerous,  satisfactory  results  were  made,  yet  it  was  evident  in  the 
experience  of  all  that  the  dozer  could  be  most  effectually  used 
early  while  the  hoppers  were  small  and  could  not  fly,  and  espec¬ 
ially  where  the  dozer  was  driven  rapidy  over  standing  alfalfa  from 
8  inches  to  12  inches  high;  although  it  was  demonstrated  that 
large  full  grown  grasshoppers  could  be  caught  and  killed  in  the 
same  manner  early  in  the  morning  after  a  shower  or  heavy  dew 
when  the  hoppers  would  be  wet  and  numb  from  cold  and  too 
stupid  to  fly. 

Early  one  morning  in  August,  after  an  evening  shower,  the 
writer  observed  that  a  piece  of  alfalfa  was  literally  yellow  with 
grasshoppers  that  had  climbed  to  the  top  of  the  stems  to  catch  the 
warmth  of  the  first  rays  of  the  morning  sun.  A  horse  was  immedi¬ 
ately  hitched  to  the  dozer,  and  coal  oil  not  being  handy  the  pan 
was  filled  with  cold  water  onlv  from  a  ditch  near  bv  and  the 

j  j 

horse  driven  at  a  trot  through  the  standing  hay  which  was  about 
12  inches  high.  It  was  40  rods  across  the  field  and  back  and  by 
that  time  the  pan  was  full  of  grasshoppers  struggling  in  the  water. 
These  were  immediately  skimmed  out  with  a  screen  and  thrown 
into  a  milk  can  and  the  cover  put  on.  After  the  second  trip  the 
can  was  more  than  full  of  grasshoppers  pressed  in  tight.  As  there 
was  no  oil  on  the  grasshoppers  the  can  was  carried  to  the  yard 
where  a  flock  of  young  chickens  and  turkeys  fairly  covered  the 
can  after  it  had  been  turned  on  one  side,  with  the  cover  off,  and 
they  had  discovered  what  it  contained.  The  following  morning  be¬ 
ing  wet  and  cold,  we  took  an  early  start  and  in  less  than  a  half  hour 
we  had  killed  over  four  bushels  of  large  grasshoppers  on  less  than 
two  acres;  this  time  we  used  coal  oil,  as  many  hoppers  seemed  to 
escape  when  only  water  was  used. 

The  amount  of  oil  required,  will  not  exceed  a  gallon  to  the 


8 


THE  COLORADO  EXPERIMENT  STATION 


acre  and  usually  much  less.  The  oilcloth  screen  at  the  back  of 

j 

the  dozer  is  an  important  feature  as  it  does  not  allow  the  hopper 
to  stick  to  it  and  those  that  hit  it  fall  into  the  pan  and  are 
killed. 

The  wheels  attached  to  the  runners  lighten  the  draft  and  en¬ 
able  one  horse  to  pull  the  pan  to  one  side  as  explained  and  shown 
in  Plate  I.,  and  also  allows  the  pan  to  be  drawn  through  standing 
alfalfa  without  trickling  it  down  to  any  extent.  For  larger  fields  a 
longer  pan,  say  from  12  to  16  feet,  would  doubtless  be  more  eco¬ 
nomical,  but  a  long  pan  would  need  divisions  to  prevent  the  water 
from  flowing  to  one  end  011  steep  ground. 

A  good  example  of  the  destruction  of  grasshopper  eggs  by 
early  spring  or  winter  discing  of  the  alfalfa  fields,  was  seen  on  the 
farm  of  Mr.  C.  J.  Cover.  His  field  was  purple  with  bloom  with 
comparatively  few  grasshoppers  while  all  neighboring  fields  had 
been  stripped  of  bloom  by  grasshoppers. 


Bulletin  113 


June,  1606 


The  Agricultural  Experiment  Station 

OF  THE 

% 

Colorado  Agricultural  College. 


Larkspur  and  Other 
Poisonous  Plants 


BY 

GEO.  H.  GLOVER 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
FORT  COLLINS,  COLORADO 
1906 


The  Agricultural  Experiment  Station 

FORT  COLLINS,  COLORADO 


THE  STATE  BOARD  OF  AGRICULTURE 


Term 


HON.  P.  F.  SHARP,  President . 

HON.  HARLAN  THOMAS . 

HON.  JAMES  L.  CHATFIELD . 

HON.  B.  U.  DYE . . 

HON.  B.  F.  ROCKAFELLOW . 

HON.  EUGENE  H.  GRUBB . 

HON.  A.  A.  EDWARDS . 

HON.  R.  W.  CORWIN . 

GOVERNOR  JESSE  F.  MCDONALD, 
PRESIDENT  BARTON  O.  AYLESWORTH, 


Expires 


Denver  . 1907 

Denver  . 1907 

Gypsum  . 1909 

Rocky  Ford  . 1909 

Canon  City . 1911 

Carbondale  . 1911 

Fort  Collins . 1913 

Pueblo  . 1913 


l 


) 


Ex-Officio. 


A.  M.  HAWLEY,  Secretary 


EDGAR  AVERY,  Treasurer 


EXECUTIVE  COMMITTEE  IN  CHARGE 
P.  F.  SHARP,  Chairman.  B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS 


STATION  STAFF 


L.  G.  CARPENTER,  M.  S.,  Director . Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S . Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D . Chemist 


W.  PADDOCK,  M.  S . 

W.  L.  CARLYLE,  M.  S . 

G.  H.  GLOVER,  M.  S.,  D.  V.  M 
W.  H.  OLIN,  M.  S . 

R.  E.  TRIMBLE,  B.  S . 

F.  C.  ALFORD,  M.  S . 

EARL  DOUGLASS,  M.  S . 

S.  ARTHUR  JOHNSON,  M.  S. . 

B.  O.  LONGYEAR,  B.  S . 

J.  A.  McLEAN,  A.  B.,  B.  S.  A .  . 

E.  B.  HOUSE,  B.  S . 

F.  KNORR  . 

E.  R.  BENNETT,  B.  S . 

P.  K.  BLINN,  B.  S . 


. Horticulturist 

. Agriculturist 

. Veterinarian 

. Agronomist 

. Assistant  Irrigation  Engineer 

. Assistant  Chemist 

. Assistant  Chemist 

. Assistant  Entomologist 

. Assistant  Horticulturist 

. Animal  Husbandman 

. Assistant  Irrigation  Engineer 

.  Assistant  Agriculturist 

. Potato  Investigations 

Field  Agent,  Arkansas  Valley,  Rocky  Ford 


WESTERN  SLOPE  FRUIT  INVESTIGATIONS,  GRAND  JUNCTION: 

O.  B.  WHIPPLE,  B.  S . Field  Horticulturist 

ESTES  P.  TAYLOR,  B.  S . Field  Entomologist 


OFFICERS 

PRESIDENT  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S . Director 

A.  M.  HAWLEY  . Secretary 

MARGARET  MURRAY . Stenographer  and  Clerk 


Larkspur  and  Other  Poisonous  Plants. 

BY  GKO.  H.  GLOVER. 


According  to  the  last  statistics,  there  are  something  over  $50,- 
000,000  invested  in  live  stock  in  the  State  of  Colorado.  The  old 
open  range  conditions  still  prevail  to  some  extent,  and  many  of  the 
vexatious  problems  which  have  hampered  this  industry  from  its 
inception  remain  unsolved. 

I  deem  it  no  presumption  to  say  that  there  is  no  place  on  the 
face  of  the  earth  where  the  live  stock  industry  flourishes  less  hamp¬ 
ered  by  disease,  contagious  or  otherwise,  than  in  the  salubrious 
climate  of  the  arid  west. 

N ot  one  of  the  great  animal  scourges  that  have  decimated  .the 
herds  of  the  Orient  for  centuries,  and  some  of  which  have  in  the 
past  reached  our  eastern  shores,  have  ever  found  their  way  west 
of  the  Mississippi  river,  thanks  to  an  eternal  vigilance  on  the  part 
of  the  Federal  and  State  authorities.  The  loss  we  suffer  is  not  great 

from  any  one  specific  cause,  but  in  the  aggregate  become  a  heavy 
burden. 

It  has  been  estimated  that  the  loss  from  poisoning  of  stock 
on  the  open  range  in  the  State  of  Montana  is  at  least  $100,000  an¬ 
nually.  In  this  State  it  must  be  nearly  or  quite  as  great.  The 
value  of  the  animals  actually  lost  does  not,  however, 
begin  to  represent  the  loss  actually  sustained  by  the  industry  be¬ 
cause  of  the  presence  of  a  few  species  of  poisonous  weeds.  In 
many  sections  of  this  State  ranchers  have  given  up  in  despair  and 
been  forced  to  abandon  otherwise  ideal  ranges.  The  animal  mor¬ 
tality,  combined  with  the  injury  done  to  those  animals  not  actually 
destroyed,  have  curtailed  the  profits  until  the  owner  at  last  is  forced 
into  bankruptcy  and  the  ranges  are  abandoned. 

Until  the  last  few  years  no  systematic  effort  has  been  made 
to  investigate  these  poisonous  plants  of  the  western  ranges. .  Their 
identity,  poisonous  nature,  and  remedy  was  simply  a  matter  of 
common  report  among  the  stockmen. 

In  1901  the  U.  S.  Department  of  Agriculture  sent  two  ex¬ 
perts  (Chesnut  and  Wilcox),  to  Montana  to  investigate  the  plant 
poisoning  of  stock  in  that  State,  and  their  report  has  been  of  ines¬ 
timable  value  not  only  to  the  live  stock  industry  of  that  State  but 
to  the  whole  country,  more  especially  to  the  arid  West.  Other 


4 


Bulletin  113. 


bulletins  from  various  State  experiment  stations,  notably  North 
Dakota,  Idaho,  Montana,  have  followed,  and  not  only  been  of  great 
practical  benefit  to  the  stockmen  in  identifying  the  most  danger¬ 
ous  of  these  plants,  but  seems  to  have  aroused  the  spirit  of  inquiry 
on  the  part  of  scientists  for  more  extended  research  regarding  them. 

This  bulletin  is  issued  with  the  view  of  placing  before  the  farm¬ 
ers  and  stockmen  of  the  State  a  plain  and  concise  statement,  with 
illustrations,  regarding  larkspur  and  a  few  of  our  most  common 
and  most  to  be  dreaded  range  plants. 

Early  in  the  spring  of  1905  the  Colorado  Experiment  Station 
undertook  a  co-operative  experimental  investigation  of  loco  and 
larkspur  with  the  Department  of  Agriculture.  The  work  with 
loco  weeds  has  been  carried  on  throughout  the  summer  and  fall, 
with  headquarters  at  Hugo,  Colo.,  under  the  direct  supervision  of  C. 
Dwight  Marsh,  of  the  U.  S.  Department  of  Agriculture,  and  the 
report  will  follow  in  due  time. 

Poison  weeds  in  general  throughout  the  State,  with  special 
reference  to  larkspur,  has  been  the  subject  of  special  inquiry 
by  the  Experiment  Station,  at  Fort  Collins,  and  in  this  investigation 
has  been  ably  assisted  by  the  Bureau  of  Plant  Industry,  at  Wash¬ 
ington,  by  way  of  identification  of  plant,  chemical  analysis,  deter¬ 
mination  of  lethal  dose,  etc. 

Out  of  the  large  number  of  plants  known  to  be  poisonous  under 
certain  conditions  the  two  loco  weeds  known  as  white  and  purple 
loco,  and  several  species  of  larkspur,  have  been  singled  out  for 
special  investigation  at  this  time  as  they  are  held  responsible  for 
at  least  ninety  per  cent,  of  the  loss  in  this  State.  While  scattering 
reports  come  in  from  various  sections  of  the  State  of  loss  which 
can  be  attributed  unly  to  camas,  lupin,  hemlock,  and  various  others, 
in  the  great  majority  of  cases  it  is  from  the  loco  weeds  in  the  east¬ 
ern  half  of  the  State  and  larkspur  in  the  mountainous  regions. 
Nearly  every  community  of  the  State  has  been  visited  within  the 
last  year,  and  a  fair  knowledge  of  the  most  prevalent  poisonous 
weeds  obtained.  In  visiting  various  sections  of  the  State,  and  by 
correspondence  as  well,  I  find  that  unless  the  plant  under  discus¬ 
sion  is  at  hand  there  is  no  certainty  that  we  both  have  the  same 
plant  in  mind.  There  is  no  general  agreement  among  stockmen 
themselves  either  as  to  the  common  names,  identity,  or  symptoms 
from  poisoning  of  even  our  most  common  poison  weeds.  White 
loco  weed  and  rattle  weed  are  spoken  of  as  different  plants;  lark¬ 
spur  is  commonly  called  aconite;  death  camas  as  wild  onions,  etc. 
I  have  corresponded  with  different  parties  with  reference  to  the 
loss  sustained  from  larkspur,  and  upon  receiving  the  specimens 
found  them  to  be  something  entirely  different.  This,  however, 
simply  causes  some  inconvenience.  It  does  not  present  a  serious 


Larkspur  and  Other  Poisonous  Peants. 


5 


obstacle  to  their  investigation,  but  incidentally  furnishes  an  in¬ 
disputable  argument  in  favor  of  the  necessity  of  educating  the 
stockmen  as  to  their  identity  in  order  that  they  may  the  more 
effectually  avoid  them. 

In  the  realm  of  toxicology  we  are  still  groping  in  the  dark, 
and  our  best  scientists  have  laid  down  before  many  of  the  stupend¬ 
ous  obstacles  confronting  them  and  acknowledge  defeat.  Here 
are  some  of  the  difficulties  with  which  we  have  to  contend : 

i.  Some  Plants  Are  Poisonous  Only  at  Certain  Stages  of 
Growth,  The  lupine  (wild  pea — horse  beans),  are  found  growing 
in  almost  every  section  of  the  State  and  in  great  abundance  on  the 
Western  Slope,  and  in  many  places  are  cut  for  hay;  they  are  poison¬ 
ous  only  at  the  time  of  going  to  seed.  Larkspur  {Delphinium) , 
is  very  deadly  early  in  the  spring,  and  loses  its  toxicity  almost  en¬ 
tirely  at  flowering  time.  The  death  camas  ( Zygadenus  venenosus), 
growing  from  a  poisonous  bulb,  is  very  deadly  early  in  the  season, 
but  gradually  becomes  less  harmful  and  dries  up  in  July.  Sorghum 
and  kaffir  corn,  which  became  popular  forage  crops  in  the  non- 
irrigable  sections  of  eastern  Colorado,  have  produced  such  dis¬ 
astrous  results  from  feeding  green  at  certain  stages  of  growth 
that  their  cultivation  has  been  generally  abandoned.  In  Bulletin 
N°*  37,  of  the  Idaho  Experiment  Station,  is  found  the  following 
bearing  upon  this  subject :  “The  roots  of  the  wild  parsnip  or  water 
hemlock,  which  are  so  virulent  in  the  early  spring,  have  been  fed 
to  cows  in  the  late  summer  and  early  fall  without  ill  effect.  An¬ 
other  member  of  the  same  family,  the  hemlock  water  parsnip,  has 
a  root  which  is  poisonous  in  the  early  spring,  but  harmless  after 
midsummer,  while  the  roots  of  another  plant  of  the  carrot  family, 
poison  hemlock,  contain  no  trace  of  poison  during  March,  April 
or  May,  although  considerable  quantities  of  the  active  principle 
coniin  are  present  in  the  leaves  and  stems  by  May.  Later  in  the 
season  the  roots  also  become  dangerous.” 

2.  Unusual  Conditions  May  Affect  the  Quantity  of  Poison  in 
Plants:  In  sorghum  and  Kaffir  corn  a  stunted  growth,  resulting 
from  arid  conditions,  is  best  suited  for  the  development  of  prussic 
acid,  the  most  powerful  poison  known.  The  poisoning  by  Johnson 
grass  (a  near  relative  of  sorghum),  is  no  doubt  due  to  the  same 
cause,  as  shown  by  Crawford  and  by  Jeffries. 

The  common  potato  which  belongs  to  the  same  genus  as  black 
nightshade,  spreading  nightshade,  bitter  sweet,  and  other  dangerous 
plants,  contains  an  active  alkaloid  solanine  which  develops  in 
large  quantities  when  potatoes  become  green  from  exposure  to  the 
sun.  This  is  no  doubt  the  cause  of  the  sudden  and  mysterious 
death  of  horses  in  the  vicinity  of  Greeley  that  had  been  turned 
into  potato  fields  after  digging  time,  many  small  potatoes  having 


6 


Bulletin  113. 


been  left  on  the  surface  exposed  to  the  sun.  *The  wilted  leaves  of 
the  wild  cherry  are  poisonous.  In  the  eastern  section  of  the  State 
a  scrubby  cherry  is  found  growing  along  the  small  streams  and 
arroyas,  and  some  loss  in  cattle  has  been  reported.  Several  species 
of  cherry  are  found  growing  abundantly  along  the  ravines  in  the 
mountains. 

3.  Poison  Pound  in  Different  Parts  of  Plants.  Another  dis¬ 
couraging  feature  in  poisonous  plant  investigation  is  that  the  poison 
is  not  always  found  in  the  same  part  of  the  plant.  In  the  case  of 
wild  hellebore,  aconite,  showy  milkweed,  thorn  apple,  and  many 
others,  the  entire  plant  is  poisonous.  In  wild  parsnips  the 
roots  contain  most  of  the  poison.  In  lupines  and  yellow  dock 
the  seeds  are  dangerous.  In  potatoes  the  roots  may  be  harmless 
and  the  tops  poisonous.  In  the  mountain  laurel  and  wild  cherry 
it  is  the  leaves.  In  milkweeds  the  stems  are  said  to  be  poisonous. 
In  the  crowfoot  family  it  is  found  that  the  flowers  are  especially 
dangerous. 

4.  Variations  According  to  Season,  Climate,  Etc.  There  are 
other  serious  difficulties  to  contend  with  in  a  systematic  investiga¬ 
tion  of  this  subject.  The  danger  of  certain  plants  varies  according 
to  season,  climate,  character  of  soil,  etc.,  from  year  to  year.  A 
dry  season  is  generally  favorable  for  the  development  of  poison 
in  most  plants.  A  plant  may  be  poisonous  in  one  country  and 
harmless  in  another.  Jimson  weed  is  more  acfive  in  America  than 
in  Europe.  Some  plants  become  less  poisonous  by  cultivation,  such 
as  wild  hellebore  and  aconite.  Where  the  plants  contain  poison 
in  small  quantity  the  native  stock  obtain  a  certain  amount  of  im¬ 
munity  and  will  feed  without  harm  on  a  range  that  will  prove 
disastrous  to  other  animals.  The  active  principle  may  exist  per¬ 
formed  in  the  plant,  which  is  generally  the  case,  or  it  may  be  formed 
by  the  action  of  ferments  during  mastication  and  digestion. 

5.  Some  Animals  More  Susceptible  Than  Others.  Plants  in¬ 
jurious  to  one  species  are  harmless  to  others.  The  horse,  mule, 
and  goat  eat  poison  ivy  with  impunity.  Clover  and  alfalfa  may 
cause  a  true  intoxication,  with  bloating,  under  certain  conditions,  in 
ruminants;  horses  pasture  upon  the  green  plant  without  danger. 
Individuals  of  the  same  species  show  a  wide  divergence  of  sus¬ 
ceptibility  to  poisons.  As  has  been  well  said,  “What  is  one  man’s 
meat  is  another  man’s  poison.”  Poison  ivy  produces  a  violent 
inflammation  of  the  skin  on  most  persons.  Some  will  escape  and 
are  apparently  immune  at  one  time,  and  equally  as  susceptible  at 
another  period  of  life. 

Throughout  the  vegetable  kingdom,  from  bacteria  all  the  way 
up  to  the  mighty  oak,  we  find  species  of  plants  poisonous  under 
certain  conditions,  but  few  of  them  poisonous  under  all  conditions. 


7 


Larkspur  and  Other  Poisonous  Plants. 

CONDITIONS  UNDER  WHICH  POISONOUS  PLANTS  ARE  EATEN. 

Most  poisonous  plants  are  bitter  and  are  avoided  by  animals. 
When  confined  to  a  certain  range  and  not  interfered  with,  they 
learn  to  avoid  them,  but  are  frequently  poisoned  while  being  moved 
from  one  locality  to  another.  When  an  animal  is  hungry  it  will 
eat  weeds  that  it  would  not  otherwise  touch.  While  driving  the 
held  at  the  time  of  the  roundup  or  to  market  they  will  be  seen 
reaching  for  the  tops  of  weeds  that  at  other  times  would  not  be 
molested.  It  is  a  matter  of  common  observation  that  the  greatest 
amount  of  poisoning  occurs  under  these  conditions,  and  the  rea¬ 
sons  assigned  are  that  animals  when  driven  for  some  distance  be¬ 
come  ravenously  hungry  and  have  not  time  to  make  the  same 
choice  of  forage  plants  as  when  at  rest. 

The  time  of  greatest  danger  is  during  or  immediately  after  a 
rain  or  snow  storm  in  the  spring  months.  Alfalfa,  whether  green 
or  cured,  is  known  to  be  much  more  dangerous  for  cattle  and 
sheep  when  wet  from  rain  or  dew.  This  seems  to  be  the  case  with 
some  poisonous  plants,  especially  larkspur.  The  explanation  most 
commonly  proposed  for  this  phenomenon,  however,  is  that  when 
the  ground  is  wet  the  roots  are  more  readily  pulled  and  eaten,  and 
being  much  more  poisonous,  the  danger  is  enhanced. 

COMMON  salt  AS  A  PREVENTIVE  AND  ALKALI  AS  A  SUBSTITUTE. 

There  seems  to  be  a  diversity  of  opinion  among  stock  raisers 
as  to  whether  alkali,  which  is  found  in  abundance  in  many  sections 
of  the  State,  is  a  complete  substitute  for  common  salt.  There 
are  several  reputable  stockmen  on  the  Western  Slope,  whose  suc¬ 
cess  in  business  recommends  their  judgment,  that  have  not  salted 
their  cattle  for  several  years,  and  claim  that  in  withholding  the  salt 
they  lessen  the  liability  to  poisoning,  and  cattle  at  least  do  just  as 
well  without  it.  On  the  other  hand,  equally  as  responsible  parties 
hold  that,  if  salt  is  not  supplied,  the  animals  develop  a  taste  for 
acrid  plants,  and  thus  the  danger  is  increased. 

While  we  have  no  definite  information  at  hand  bearing  upon 
this  subject,  it  would  seem  that  from  a  physiological  standpoint 
alkali,  which  is  mostly  sulfate  of  soda,  sulfate  of  magnesium,  and 
carbonate  of  soda,  would  in  a  measure  take  the  place  of  common 
salt,  which  is  chlorid  of  sodium,  but  could  not  entirely  do  so.  The 
assumption  that  lack  of  salt  in  some  form  causes  animals  to  more 
readily  partake  of  noxious  weeds  seems  entirely  reasonable. 

The  drinking  of  alkali  water  is  said  to  cause  the  death  of 
cattle  and  sheep,  with  symptoms  much  like  poisoning  from  larkspur. 
The  reason  for  this  assumption  is  due  in  a  large  measure  to  the 
fact  that  when  animals  are  poisoned  from  various  weeds  they  im- 


8 


Bulletin  i  13. 


mediately  start  for  water  and  are  found  after  death  lying  adjacent 
to  water  holes,  springs,  and  accessible  streams.  In  some  places  the 
springs  of  purest  water  have  been  fenced  in,  the  owner  erroneously 
believing  the  water  to  have  poisoned  his  stock.  For  the  reasons 
already  assigned,  the  finding  of  a  number  of  sick  or  dead  animals 
within  a  few  yards  of  a  spring  has  frequently  caused  the  owner 
to  suspect  his  neighbor  of  having  maliciously  placed  some  violent 
poison  in  the  spring. 


preventive;  measures. 

Prevention  is  better  than  cure.  The  all  important  question 
with  the  stockmen  is  how  to  prevent  poisoning.  The  loss  from  this 
source,  even  though  it  be  small,  cuts  directly  into  the  profits.  Reme¬ 
dies,  no  matter  how  efficacious,  will  only  save  a  small  percentage  of 
them.  As  previously  stated,  poisoning  is  more  likely  to  occur  while 
they  are  being  handled,  but  the  aggregate  loss  will  show  that  the 
great  majority  are  simply  found  dead  near  a  water  hole  adjacent 
to  a  patch  of  larkspur.  There  is  no  such  thing  as  complete  immunity 
from  poisoning  so  long  as  animals  are  exposed  to  the  weed.  If  the 
weed  could  in  some  way  be  eradicated,  the  problem  would  be  solved. 
The  possibility  of  displacing  poisonous  plants  with  forage  plants  has 
led  to  some  experiments  along  this  line  by  the  Montana  Experiment 
Station.*  The  forage  plants  tried  were  the  smooth  brome  grass  and 
the  western  wheat  grass,  or  “blue  joint.”  It  will  require  several 
years  to  determine  finally  whether  this  is  possible. 

In  the  report  of  Chesnut  and  Wilcox,  on  “The  Stock  Poison¬ 
ing  Plants  of  Montana/’**  is  found  the  following: 

The  short-awned  brome  grass  (Bromus  marginatus  Nees),  a  native 
species,  is  spreading  rapidly  in  a  number  of  localities  in  various  parts  of 
the  State.  In  some  places  this  grass  had  already  displaced  all  other  native 
plants  and  occupied  the  ground  completely.  On  a  cattle  ranch  near  Au¬ 
gusta  it  has  invaded  a  timothy  meadow  and  entirely  killed  out  the  timothy 
as  far  as  it  has  spread.  This  brome  grass  produces  a  heavy  crop  of  hay, 
and  a  few  stockmen,  having  noticed  its  good  properties,  are  preparing  to 
save  seed  for  sowing  upon  other  parts  of  the  ranges.  Although  work  along 
this  line  extends  over  only  three  or  four  years,  the  outlooK  is  promising, 
and  it  is  perhaps  not  unreasonable  to  hope  that  by  assisting  the  distribution 
of  the  brome  grasses,  blue  joint,  and  other  aggressive  forage  plants,  the 
quantity  of  poisonous  plants  upon  the  range  may  be  appreciably  diminished. 

This,  however,  were  it  to  succeed,  would  take  many  years. 
Introducing  forage  plants  to  supplant  others  in  their  natural  habi¬ 
tat,  on  the  millions  of  acres  in  Colorado  ranges  is  not  sufficiently 
promising  to  warrant  much  hope  of  its  consummation  in  many 
years  to  come,  if  ever. 

The  feasibility  of  grubbing  out  the  weeds  is  worthy  of  more 


*  Bulletins  Nos.  15  and  45,  Montana  Experiment  Station. 

**  Bulletins  Nos.  20  and  24,  U.  S  Department  of  Agriculture. 


Larkspur  and  Other  Poisonous  Plants. 


9 


serious  consideration.  This  I  have  advised  in  some  cases  where 
the  plants  were  growing  in  a  circumscribed  area.  It  is  rather  sur¬ 
prising  the  amount  of  land  that  can  be  cleared  by  three  or  four 
men  in  a  day.  In  one  instance  a  patch  of  aconite  covering  possibly 
two  acres  that  had  been  a  source  of  trouble  for  several  years  was 
finally  cleaned  out  in  half  a  day  by  four  men.  Of  course,  where 
the  plants  are  well  distributed  over  a  range  of  several  thousand 
acres  this  would  be  impracticable  and  all  but  impossible.  There  are 
many  instances,  however,  where  the  loss  in  one  year  would  pay 
for  the  digging  out  of  every  plant.  The  results  of  observation  and 
experiment  are  conclusive  that  the  most  dangerous  period  is  in  the 
early  spring,  and  that  the  plants  not  only  become  unpalatable  but 
cease  to  be  dangerous  at  the  flowering  period.  The  most  effective 
means  of  prevention  is  for  the  stockman  to  become  thoroughly  fa¬ 
miliar  with  the  different  species  of  larkspur,  and  having  located 
them,  pasture  the  animals  on  non-infected  ranges  until  the  danger¬ 
ous  period  is  past.  The  time  that  they  can  be  placed  on  larkspur 
pastures  will  depend  upon  the  season  and  the  altitude.  At  high 
elevations  (9,000  to  11,000  feet)  it  would  not  be  safe  before  about 
the  15th  of  July.  West  of  Fort  Collins,  at  an  altitude  of  5,500 
feet,  the  stockmen  feel  quite  safe  by  the  20th  of  June. 


10 


Bulletin  113. 


Poisonous  Plants. 


larkspur.  ( Delphinium .) 

There  can  be  no  question  but  that  the  several  species  of  larks¬ 
pur  growing  native  in  the  mountainous  districts  of  Colorado  are 
a  greater  source  of  loss  to  the  stockmen  than  all  other  weeds 
combined.  While  the  larkspur  is  confined  to  the  mountainous 
regions,  it  nevertheless  holds  true  that  in  the  aggregate  mortality 
throughout  the  State  from  poisonous  plants  larkspur  takes  second 
place  only  to  loco.  We  have  no  statistics  at  hand  whereby  we  can 
estimate,  with  any  degree  of  accuracy,  the  total  loss,  but  judging 
from  the  reports  of  other  western  states  and  from  information  re¬ 
ceived  from  most  every  section  of  the  State,  it  would  seem  that 
$40,000  annually  is  a  conservative  estimate. 

There  are  four  species  of  larkspur  found  growing  abund¬ 
antly  in  the  middle  and  western  portion  of  this  State,  and  one 
found  growing  sparingly  in  the  eastern  plains  section.  Other  species 
have  been  found  in  isolated  places,  but  have  not  been  especially 
accused  of  doing  any  harm,  and  their  toxicity  has  not  been  proved. 
The  four  species  found  in  the  greatest  abundance  and  named  in 
the  order  of  their  importance,  are  purple  larkspur,  Delphinium 
Nelsonii,  Greene;  tall  larkspur,  Delphinium  elongatum,  (Rydb.)  ; 
D.  Geyeri,  (Greene),  and  D.  Barbeyi,  (Huth).  These  all 
have  the  same  characteristic  flowers,  and  are  found  growing  in  the 
mountains  at  altitudes  from  5,000  to  11,000  feet.  The  D.  Penardii 
(Huth),  has  a  white  flower  and  may  be  seen  growing  adjacent  to 
streams  and  in  the  arroyas  on  the  plains  as  far  east  as  the  State 
line. 

In  June  last  this  letter  of  inquiry  was  addressed  to  one  thous¬ 
and  stockmen  in  the  State,  and  a  fairly  liberal  response  was  re¬ 
ceived. 

Dear  Sir: 

The  Experiment  Station  is  conducting  an  investigation  in  connection 
with  the  U.  S.  Department  of  Agriculture,  on  the  range  plants  of  the 
State,  poisonous  to  stock,  and  desires  the  benefit  of  your  experience  and 
observations  on  the  subject.  The  information  obtained  will  be  collated 
and  published  and  copies  will  be  sent  to  all  who  have  assisted  with  informa¬ 
tion  and  experience. 

The  Experiment  Station  will  more  particularly  take  up  the  question 
of  larkspur  and  poison  plants  other  than  loco. 

Please  answer  as  many  of  the  questions  as  you  can,  and  forward  the 


Larkspur  and  Other  Poisonous  Plants. 


i  i 


blank  promptly.  Will  you  please  send  me  samples  of  any  plants  you  have 
reason  to  thing1  cause  trouble,  including  the  flower,  if  possible. 

•  GEO.  H.  GLOVER, 

Veterinarian. 

COLORADO  AGRICULTURAL  EXPERIMENT  STATION 

FORT  COLLINS,  COLO. 


LARKSPUR  INVESTIGATION. 

1.  My  name  is . 

P.  O.  Address . 

2.  I  have  had  experience  with . on  the 

Kind  of  stock 

range  extending  over . years;  on  ranges  as  follows: 

.  in  the  . 

Give  location  Foothills 

. at  elevation  of . .  . 

3.  I  have  lost . attributed  to  eating 

Kind  of  stock 

larkspur. 

4.  The  loss  has  been.  .  . . per  cent  annually  from . 

years’  experience. 

5.  The  greatest  loss  of  any  one  year  was . %  which 

was  in . year . 

State 

6.  Of  those  attacked . %  died  (  or  better,,  state 

how  many  were  attacked  and  how  many  died,  giving  size  of  herd). 

7.  What  was  your  remedy  for  larkspur? . 

8.  The  most  successful  remedy  has  been . 

9.  State  what  remedies  or  methods  of  treatment  did  not  succeed . 


10.  Send  samples  of  what  you  know  as  larkspur. 

11.  Do  you  believe  larkspur  to  kill  simply  by  bloat  like  alfalfa? 


Reasons  . 

12.  About  what  is  the  altitude  of  your  pasture . 

13.  About  what  time  of  year  do  you  experience  the  greatest  loss  from 

larkspur?  . 

14.  About  what  kind  of  livestock  has  suffered  most  in  your  vicinity  from 

this  cause?  . 

15.  Do  you  believe  lack  of  salt  caused  them  to  eat  more  of  this  plant  than 

they  would  otherwise? . 

16.  Do  you  believe  that  rain,  snow,  etc.,  aggravate  the  trouble? . 


17.  Are  animals  in  poor  condition  more  liable  to  be  attacked  than  those  in 

good  condition? . 

18.  Are  they  more  liable  to  be  attacked  after  or  during  a  long  drive? 


Name 


12 


Bulletin  113. 


The  response  to  this  letter  of  inquiry  was,  in  some  respects, 
disappointing.  Of  those  who  were  courteous  enough  to  reply, 
93  per  cent  had  experienced  loss  from  various  poisonous  weeds, 
ranging  from  one-half  of  one  per  cent,  to  sixty  per  cent.  Seventy- 
five  per  cent,  of  those  replying  acknowledged  that  while  they  had 
lost  animals  from  some  kind  of  poisoning,  yet  they  were  not  familiar 
with  larkspur,  and  expressed  a  profound  ignorance  regarding  the 
identity  of  the  plants  mentioned.  All  kinds  of  harmless  weeds 
were  sent  to  the  Station,  presuming  them  to  be  larkspur,  or  some¬ 
thing  equally  as  dangerous.  Four  expressed  the  opinion  very 
emphatically  that,  while  their  ranges  were  infested  with  larkspur, 
yet  they  had  suffered  no  inconvenience  and  did  not  expect  to  so 
long  as  the  range  was  not  overstocked  and  plenty  of  salt  was  pro¬ 
vided  . 

In  answer  to  question  No.  4,  the  loss  ranged  from  one  to  five 
per  cent.,  covering  a  period  of  from  one  to  twenty  years.  In  ques¬ 
tion  No.  5  the  greatest  loss  in  any  one  year  ranged  from  one  to 
sixty  per  cent.  The  latter  being  in  case  of  a  small  herd  being 
driven  through  the  mountains  where  they  came  near  being  ex¬ 
terminated. 

Of  those  attacked  the  report  was  that  from  five  to  one  hundred 
per  cent.  died.  The  remedies  suggested  were  as  follows : 

Bleeding  from  the  ear-vein  or  under  the  tail. 

Tapping  through  the  side  and  allowing  the  gas  to  escape. 

Turning  the  head  uphill  when  down.  Chasing  the  poisoned  animals, 
and  keeping  them  on  the  run. 

Slitting  the  skin  in  the  forehead  and  pouring  in  turpentine. 

Tobacco,  internally,  in  uncertain  quantities. 

Bacon,  cut  into  small  strips  and  forced  down  the  throat. 

Linseed  oil  given  by  drench. 

Bleeding  and  tapping  through  the  side  appear  to  be  the  uni¬ 
versal  remedies,  and  most  every  answer  contained  an  emphatic 
statement  that  animals  could  be  saved  by  this  treatment. 

Of  the  specimens  sent,  about  one-half  proved  to  be  larkspur. 
In  answer  to  question  No.  11,  forty  per  cent,  believed  larkspur 
to  kill  by  bloat,  like  alfalfa,  and  that  if  they  could  be  tapped  soon 
enough,  would  all  recover.  The  altitude  ranged  all  the  way  from 
5,000  to  11,000  feet.  There  was  general  agreement  that  the  early 
spring  was  the  most  dangerous  period.  A  few  had  lost  cattle 
and  sheep  in  August,  at  high  elevations.  The  greatest  loss  was  re¬ 
ported  in  cattle;  next  in  sheep,  and  a  few  reported  loss  of  horses. 

In  answer  to  question  No.  15,  seventy-one  per  cent,  replied  in 
the  negative,  and  the  remaining  twenty-nine  per  cent,  were  sure 
that  lack  of  salt  caused  an  abnormal  appetite  for  noxious  weeds. 
Practically  all  agreed  that  rain  and  snow,  in  some  way,  greatly 
aggravated  the  trouble. 


13 


Larkspur  and  Other  Poisonous  Puanis. 

In  question  No.  17,  the  answers  were  about  equally  divided 
between  those  who  believed  that  condition  of  animals  had  nothing 
to .  do  with  the  case,  and  those  who  were  confident  that  poor 
animals  were  more  susceptible  and  those  who  thought  fat  animals 

more  liable.  All  the  answers  to  No.  18  were  in  the  affirmative 
except  two. 

The  value  of  the  information  gained  by  this  inquiry  consists 
largely  in  the  fact  that  it  reveals  in  a  measure  the  extent  of 
the  loss  from  these  noxious  herbs  and  lays  bare  before  us  evidence 
that  the  stockmen  possess  no  reliable  information  regarding  them 
or  any  other  of  the  poisonous  weeds.  In  one  thing,  however,  they 
are  all  agreed,  viz. :  some  poisonous  plants  are  killing  the  animals 
from  year  to  year  and  that  it  has  become  a  heavy  burden.  Not 
knowing  anything  better,  the  old  fashioned  remedies,  bleeding, 
bacon  rinds,  turpentine,  etc.,  are  tried,  with  indifferent  results. 

This  is  not  surprising,  however,  when  we  come  to  consider 
that  it  is  only  within  the  last  few  years  that  this  subject  has  received 
any  attention  at  the  hands  of  investigators,  and  even  now  very  little 
reliable  information  can  be  had  regarding  the  chemistry,  physiology, 
01  satisfactory  antidotes  for  the  many  deadly  plants  inhabiting 
the  western  ranges. 

Description,  History ,  and  Habitat.  While  there  are  several 
species  of  larkspur  growing  in  the  State,  there  are  only  two,  the 
tall  and  the  purple,  found  growing  in  sufficient  quantities  to  warrant 
a  serious  consideration.  They  both  have  the  characteristic  spur 
shaped  flower  (cockspur),  but  in  other  respects  differ  widely.  The 
tall  ( Delphinium  elongatum)  grows  from  one  to  five  feet  high,  and 
has  a  pale  blue  flower.  The  leaves  are  broad  and  from  two  to  six 
inches  in  diameter,  and  greatly  resemble  those  of  the  wild  geranium. 
It  is  found,  growing  along  the  streams,  in  moist  places,  and  upon 
the  north  side  of  mountains  at  an  altitude  up  to  9,000  feet.  From 
the  middle  of  March  to  the  4th  of  July,  according  to  altitude,  is  the 
dangerous  period  for  this  plant.  The  tall  larkspur  resembles  the 
aconite  (Monkshood),  both  in  its  general  appearance  and  toxic 
effect  upon  animals.  They  should  not  be  confused,  however,  if 
careful  examination  of  the  flower  is  made,  the  larkspur  having  an 
appendage  in  appearance  like  a  cock’s  spur;  while  the  aconite  has 
a  flower  dark  purple  in  color  and  with  a  top  resembling  a  hood, 
hence  the  name  monkshood.  From  the  reports  in  other  western 
states,  especially  Montana,  it  would  seem  that  the  purple  larkspur, 
which  is  more  generally  eaten  by  sheep,  is  the  more  disastrous  of 
the  two.  In  this  State  it  is  quite  the  reverse.  The  tall  larkspur 
is  more  abundant  and  the  major  part  of  the  mortality  is  among 
cattle. 

The  purple  larkspur  rarely  exceeds  two  feet  in  height.  The 


14 


Bulletin  113. 


leaves  appear  on  a  long  stem  in  the  form  of  a  cluster,  are  finely 
divided,  and  in  appearance  are  very  different  from  the  large  oval 
leaf  of  the  species  previously  mentioned.  The  flowers  have  the 
same  appearance,  save  in  color,  which  varies  from  a  deep  blue 
to  a  dark  rich  purple.  It  grows  at  high  altitudes.  In  the  moun¬ 
tains  west  of  the  Roaring  Fork  it  was  found  growing  at  11,000 
feet,  and  at  lower  altitudes  had  been  seen  in  full  bloom  on  the  20th 
of  April.  Very  little  damage  had  been  reported  from  this  plant 
after  May  1st.  As  both  species  of  larkspur  do  their  damage  before 
the  flowering  season,  it  is  of  the  greatest  importance  that  stockmen 
familiarize  themselves  with  the  appearance  of  this  plant  before 
bloom  and  assiduously  avoid  it. 

Symptoms  of  Poisoning.  The  symptoms  of  larkspur  poisoning 
are  similar  to  those  produced  by  aconite.  The  first  thing  noticed 
is  a  stiffness.  The  back  appears  to  be  arched  and  the  legs  are 
carried  wide  apart.  There  is  usually  some  frothing  at  the  mouth. 
The  animal  stumbles  and  falls,  several  times,  and  trembles  violently. 
The  throat  is  affected  and  there  is  persistent  swallowing. 
Breathing  is  rapid  and  shallow.  In  severe  cases  violent  convul¬ 
sions  come  on,  in  one  of  which  the  animal  finally  dies. 

Treatment.  In  cases  where  the  bloating  becomes  extreme, 
we  have  not  only  the  intoxication  from  the  active  poison  in  the 
plant  to  contend  with,  but  the  excessive  accumulation  of  gas  be¬ 
comes  a  mechanical  condition,  which  of  itself  hastens  or  may  even 
become  the  principal  factor  in  causing  the  death  of  the  animal.  The 
practice  of  tapping  through  the  left  side  into  the  rumen  for  the 
purpose  of  allowing  the  gas  to  escape  in  extreme  cases  is  good 
treatment  and  has  no  doubt  been  the  means  of  saving  many  an 
animal.  Every  stockman  should  carry  a  trocar  with  him  while 
riding  the  range  during  the  spring  months  to  use  for  this  opera¬ 
tion,  and  not  be  obliged  to  use  the  jack  knife.  The  instrument  can 
be  purchased  at  hardware  stores  for  one  dollar  or  less.  The  re¬ 
sults  of  using  it  in  the  case  of  bloat  in  cattle  or  sheep  from  any 
cause  are  usually  perfectly  satisfactory,  and  the  animals  will  not 
shrink  in  condition  as  is  usually  the  case  from  using  a  knife. 

As  previously  stated,  the  most  trouble  occurs  while  the  animals 
are  being  moved  from  place  to  place  during  the  spring  months. ' 
In  most  cases  the  man  is  alone  and  may  have  several  poisoned  at 
the  same  time.  He  is  therefore  poorly  equipped  to  undertake  any 
complex  treatment.  His  treatment  must  be  simple,  effective,  and 
done  without  delay.  The  practice  of  turning  them  so  that  they 
lie  with  the  head  up  hill  is  to  be  commended,  as  it  relieves  the 
pressure  on  the  lungs  and  heart  from  the  distended  bowels.  Bleed¬ 
ing  is  uniformly  recommended  and  practiced  by  the  sheep  herders 
and  cow  men.  It  is  difficult  to  see  how  it  can  be  of  any  benefit, 


Larkspur  and  Other  Poisonous  Plants. 


and  experimentally  it  has  not  proved  to  be  so.  One  gentleman 
from  the  YVestern  Slope,  who  besides  being  a  successful  ranch- 

m,a: was  also  a  graduate  physician,  explains  the  beneficial  results 
o  beeding  as  follows:  “It  relieves  the  passive  congestion  in¬ 
duced  by  the  paralyzing  effect  of  the  poison  upon  the  heart.” 

It  is-  less  than  fifty  years  since  bleeding  was  practiced  on  the 
lower  animals  as  well  as  on  the  human,  for  every  imaginable  com¬ 
plaint,  and  it  was  considered  uniformly  efficacious.  It  has  now 
been  discontinued  save  m  rare  instances.  It  is  a  question  whether 
the  animals  would  not  do  just  as  well  or  better  if  left  entirely  alone 
The  principal  effect  of  larkspur,  like  aconite,  is  to  depress  the  heart 
action ;  therefore  the  animal  should  not  be  chased  or  excited. 

•  4.u  ^  wouIf  be  hard  to  conceive  of  a  treatment  more  disastrous 
in  this  case  than  tobacco.  Its  action  would  be  much  like  the  poison 
and  disastrous  in  the  extreme.  The  use  of  bacon  would  be  absurd 
Lard  could  be  given  in  this  case  as  it  is  in  strychnine  poisoning  in 
dogs.  Its  value  consists  in  mechanically  retarding  the  absorption 
of  the  poison.  The  practice  of  slitting  the  forehead  and  pouring 
m  turpentine  is  too  absurd  for  serious  consideration.  This  along 
with  many  other  absurdities  practiced  in  the  name  of  curative 
medicine  is  to  be  looked  upon  as  a  relic  of  the  superstitions  of 
lormer  days,  and  should,  along  with  the  magic  of  the  witches 

mess  pot,  be  relegated  to  the  company  of  the  empiricisms  of  a  less 
enlightened  age. 


As  shown  m  the  account  of  experiments  which  follow,  we 
have  at  least  two  remedies  which  possess  real  antidotal  value.  These 
cases  of  poisoning  occur  in  almost  every  instance  in  mountain 
ranges,  far  removed  from  any  immediate  assistance,  and  under 
the  worst  conditions  imaginable.  The  remedies,  whatever  they 
are,  must  be  something  that  can  be  carried  on  horse  back  and  easily 
and  quickly  given.  As  a  chemical  antidote,  potassium  permangan¬ 
ate  and  aluminum  sulfate  in  equal  parts  in  doses  of  from  thirty 
to  fifty  grains  (five  to  ten  grains  for  sheep),  dissolved  in  at  least 
a  pint  of  water,  is  given  at  one  dose,  by  drench.  This  remedy 
so  highly .  recommended  by  Chesnut  and  Wilcox  in  their  Montana 
investigation,  has  been  repeatedly  tried  at  this  Station  with  most 
satisfactory  results.  I  believe  this  remedy  to  be  a  practical  one 
for  the  stockmen.  When  operating  within  easy  access  to  water 
the  powders  can  be  carried  ready  for  solution  and  given  without 
much  delay.  With  slight  inconvenience  the  solution  can  be  carried 
ready  for  use.  It  is  important  to  see  that  the  powder  is  completely 
dissolved.  It  should  then  be  given  at  one  dose,  exciting  the  animal 
as  little  as  possible.  A  number  of  drugs  have  been  tried  experi¬ 
mentally  upon  sheep  and  rabbits,  with  the  hope  of  finding  some¬ 
thing  easy  of  application  that  would  counteract  the  depressing  effect 


i6 


Bulletin  113. 


of  the  poison  upon  the  heart  and  circulation.  Most  of  them  were 
disappointing  in  the  extreme.  Stimulants  are  indicated  (alcohol* 
camphor,  ammonia,  strychnine,  etc.,),  and  all  are  more  or  less 
beneficial.  Glonoin  (nitro-glycerine)  injected  hypodermically,  re¬ 
vived  the  heart’s  action  and  abated  the  alarming  symptoms  for  a 
time.  This,  however,  did  not  appear  to  be  a  true  physiological 
antidote. 

Atropine,  given  in  one  half  to  one  grain  doses,  hypodermically, 
gave  satisfactory,  and  in  some  cases,  astonishing  results.  Every 
stockman  should  keep  on  the  ranch  a  hypodermic  syringe  for  in¬ 
oculating  his  calves  against  blackleg,  and  in  this  way  become 
familiar  with  the  use  of  the  instrument.  The  atropine  tablets  can 
be  secured  at  any  drug  store.  A  small  vial  of  boiled  water  may 
be  carried  in  the  vest  pocket  and  the  remedy  quickly  prepared  and 
given  to  a  number  of  poisoned  animals.  The  dose  is  one-half  to  one 
grain  for  cattle  and  horses  and  one-twentieth  of  a  grain  for  sheep. 
I  have  no  hesitancy  in  strongly  recommending  potassium  perman¬ 
ganate,  when  used  in  the  way  indicated,  as  a  chemical  antidote, 
and  the  atropine  as  a  physiological  antidote.  Either  drug  may  be 
repeated,  if  necessary,  in  half  an  hour.  In  case  these  remedies 
are  not  at  hand,  any  one  of  the  following  stimulants  might  be 
tried :  Whiskey,  in  two-ounce  doses,  for  cattle  or  horses ;  aromatic 
spirits  of  ammonia,  two  ounces  well  diluted  with  water,  for  cattle 
and  horses.  Spirits  of  camphor,  one  ounce.  Fluid  extract  of  bel¬ 
ladonna,  two  drachms.  Nitrous  ether,  two  ounces.  For  sheep, 
give  one-fourth  the  amount. 

Results  of  Experiments.  In  accordance  with  an  agreement 
entered  into  with  the  Department  of  Agriculture,  whereby  we  were 
to  conduct  a  co-operative  investigation  of  loco,  larkspur,  and  other 
poisonous  plants,  larkspur  was  gathered  at  intervals  throughout 
the  spring  months.  The  first  was  gathered  on  April  26th,  when 
it  was  about  four  inches  high,  and  the  last  on  June  12th,  at  which 
time  the  flower  was  in  full  bloom  and  the  plants  were  beginning  to 
dry  up.  It  was  dug  with  roots  attached  and  after  drying  ten  days, 
was  sent  in  five  pound  packages  to  the  Bureau  of  Plant  Industry, 
U.  S.  Department  of  Agriculture. 

On  October  10th  Doctor  Crawford  reported  as  follows: 

“The  method  used  in  testing  the  physiological  activity  of  plants  was 
to  weigh  accurately  five  grams  of  the  powdered  plants,  then  extract  this 
over  night  with  twenty  c.  c.  of  water,  and  ten  c.  c.  alcohol  added  mainly  as 
a  preservative.  The  following  day  the  extraction  with  water  and  squeezing 
was  continued  until  the  fluid  became  colorless.  The  fluid  was  then  evaporated 
to  dryness  in  vacuo  about  40°  C.,  and  the  residue  made  up  to  30  c.  c.  with 
water.  Any  number  of  c.  c.  would  do  as  well.  The  alcohol  was  given  off 
in  vacuo. 


PLATE  I.* 

Purple  Larkspur,  Young  Plant. 

.  ( Delphinium  bicolor ) 

Almost  indistinguishable  from  D.  Nelsonii  of  Colorado. 

*  All  Plates,  except  Plate  VIII.,  are  from  U.  S.  Dept,  of  Agriculture,  Chesnut  and  Wilson 
Bulletin  26,  Div.  of  Botany. 


PLATE  II, 

Purple  Larkspur  in  Flower. 

(. Delphinium  bicolor,  D.  Nelsojiii  Greene) 


PLATE  III. 

Tall  Larkspur. 

Shown  as  D.  glaucum  in  Bull.  26,  Div.  of  Botany,  Dept,  of  Agriculture. 
Much  the  same  as  D.  elongatum  of  Colorado. 


PLATE  IV. 
Death  Camas 
(. Zygadenus  venenosus.) 


Larkspur  and  Othkr  Poisonous  Plants.  iy 

The  First  Batch  Collected  April  26tli,  1905. 

CauSeaCM°'disturbeance.t0  a  P‘S  <subcutaneo«sly).  weight  730  grams. 

3  c.  c.  in  guinea  pig,  no  symptoms. 

6  c.  c.  in  guinea.  Killed. 

6  c.  c.  injected  into  guinea  pig,  28  5  grams,  killed  in  3  3  minutes. 

4  c.  c.  injected  into  guinea  pig,  352  grams,  no  symptoms 

Repeated: 

5  c.  c.  killed  guinea  pig  weighing  19  6  grams.  Died  in  55  minutes. 

4  c.  c.  injected  into  guined  pig,  299  grams.  No  symptoms. 

Evidently  lethal  dose  for  this  solution  lay  between  4  to  5  c.  c. 

Second  Stage,  Gathered  May  16tli,  1905. 

Solution  corresponding  to  4  c.  c.  of  No.  1  caused  no  symptoms  in 
guinea  pig  weighing  445  grams,  while  5.3  c.c.  gilled  one  of  350  grams,  but 
death  was  delayed  longer  than  with  extract  of  first  stage. 

Third  Stage,  Gathered  in  June,  1905. 

Solution  corresponding  to  4  c.  c.  caused  no  symptoms  in  guinea  pig 
weighing  376  grams. 

5.3  c.  c.  caused  no  symptoms  in  guinea  pig  weighing  500  grams. 

6.6  c.  c.  caused  no  symptoms  in  guinea  pig  weighing  480  grams. 

.  Evidently  lethal  dose  is  much  higher  and  the  plant  loses  much  of  its 
activity  in  development. 

This  report  is  very  conclusive  in  proving  that  the  plant  con¬ 
tains  an  active  poison,  and  further  in  substantiating  the  claims  of 
experienced  observers  that  the  plant  loses  much  of  its  toxic  proper¬ 
ties  as  it  approaches  the  flowering  period. 

Correspondence  with  those  who  have  had  wide  experience  with 
larkspur  elicits  the  fact  that  animals  often  eat  considerable  quan¬ 
tities  of  the  plant  without  injury.  Rabbis  lived  for  days  on  a 
on  a  spare  diet  of  dried  purple  larkspur,  but  succumbed  readily  to  the 
more  tempting  bait  of  the  green. 

It  is  not  the  purpose  of  this  bulletin  to  give  a  detailed  report 
of  laboratory  experiments.  The  results  will  be  briefly  summarized 
at  the  conclusion  of  this  report.  As  proof,  however,  of  the  state¬ 
ments  made  regarding  the  difficulties  of  securing  accurate  knowl¬ 
edge  of  the  toxic  properties  of  plants  under  any  and  all  conditions, 
the  following  experiment  is  interesting  as  well  as  instructive : 

Seven  and  one-half  grams  of  dried  purple  larkspur  fed  to 
each  of  three  rabbits  on  April  20th.  No  results. 

Seven  and  one-half  grams  of  fresh  purple  larkspur  from  same 
patch  fed  April  25th  to  each  of  three  rabbits.  Two  showed  slight 
uneasiness,  and  one  was  bloated  a  little.  One,  showing  less  effect 
than  the  others,  had  eaten  but  three  and  one-half  grams. 

On  May  1st  a  like  quantity  from  the  same  patch  was  given  to 
the  same  rabbits  under  similar  conditions.  Results,  two  died,  and 
the  other  distressed. 

O11  June  15th,  the  plants  from  the  same  source  being  in  full 
bloom,  but  the  leaves  and  stems  dry,  were  fed  to  rabbits.  Al- 


i8 


Bulletin  i  13. 


though  very  hungry,  they  at  first  refused  to  eat,  but  latei  ate  laige 
quantities  of  it  without  any  ill  effects.  The  experiments  with  tall 
larkspur  were  equally  as  confusing,  fl  he  fact  that  the  plants  at  one 
period  of  growth  gave  negative  results  was  no  guaranty  that  it 
would  not  be  dangerous  at  another.  The  tall  larkspur  growing 
luxuriantly  on  the  college  campus  proved  to  be  very  active,  physio¬ 
logically,  and  furnished  the  best  specimens  for  producing  the 
physiological  effects  upon  animals.  In  the  experiments  with  anti¬ 
dotes  this  domesticated  species  was  found  to  be  very  poisonous 
while  in  bloom  in  the  middle  of  August. 

Two  other  species,  D.  Barbeyi,  (Huth)  and  D.  Geycri 
(Greene),  found  growing  sparingly  under  conditions  about  the 
same  as  the  species  mentioned,  were  found  to  be  poisonous.  Their 
relative  toxicity,  however,  was  not  considered,  as  they  were  not 
found  in  great  abundance. 

The  several  conclusions  arrived  at  with  reference  to  larkspur 
are  as  follows :  First,  at  least  eighteen  species,  and  several  varie¬ 
ties  of  larkspur,  have  been  found  growing  in  the  State.  Four  grow¬ 
ing  in  the  greatest  abundance  are  known  to  contain  an  active  poison 
in  sufficient  quantities  to  be  dangerous  to  live  stock. 

Second,  death  is  produced  as  a  result  of  the  presence  of  an 
active  poison,  and  not  from  “bloat,”  as  many  stockmen  have 
claimed. 

Third,  the  toxic  principle  of  larkspur  has  not  yet  been  de¬ 
termined  for  these  species,  but  is  probably  delphinine  and  allied 
alkaloids  present  in  other  species  that  have  not  been  fully  studied. 

Fourth,  the  plant  loses  its  toxic  qualities  as  it  approaches  the 
flowering  season  and  finally  becomes  harmless.  #  • 

Fifth,  two  species,  because  of  their  abundance,  are  doing- 
most  of  the  damage,  i.  c.,  tall  larkspur  ( Delphinium  clougcttuiii') ,  and 
purple  larkspur  ( Delphinium  Nelsonii.) 

Sixth,  stockmen  generally  have  little  knowledge  of  the  identity, 
poisonous  nature,  or  satisfactory  remedy  for  larkspur. 

Seventh,  considering  the  enormous  loss  and  the  fact  that 
larkspur  is  usually  found  in  circumscribed  areas,  it  would  seem 
feasible,  in  many  localities  at  least,  to  undertake  its  eradication  by 
the  grubbing  hoe. 

Kighth,  by  avoiding  the  areas  where  larkspur  abounds  duiing 
the  months  of  April,  May,  and  June,  the  loss  can  be  reduced  to 
the  minimum. 

Ninth,  in  potassium  permanganate  and  atropia  sulphate,  re¬ 
spectively,  we  have  a  chemical  and  physiological  antidote  of  leal 
practical  value.  Stimulants  are  indicated.  Tapping  should  be 
done  with  trocar  and  canula  high  up  on  the  left  side,  aftei  first  mak¬ 
ing  slight  incision  on  the  skin  with  a  knife.  In  case  of  extreme 


Larkspur  and  Other  Poisonous  Plants.  19 

distention  this  operation  should  not  be  delayed.  The  value  of 
bleeding  is  questionable.  All  measures  which  tend  to  depress  the 
animal,  such  as  forcible  exercise,  tobacco,  aconite,  etc.,  are  posi¬ 
tively  harmful.  If  on  sloping  ground,  the  head  should  be  turned  up 
the  hill. 

death  camas.  (Zygad 'enus  Venenosus,  Wats.) 

Other  names:  Wild  lobelia,  poison  camas,  poison  grass,  wild 
onion,  poison  sego,  mystery  grass,  wild  leek,  crow  foot. 

Description..  As  will  be  seen  from  the  accompanying  plate, 
this  plant  bears  a  strong  resemblance  to  the  wild  onion.  On  ac¬ 
count  of  its  bulb  it  has  also  been  mistaken  for  the  prairie  lilly  or 
Indian  sego.  The  bulb  of  the  sego  ( Calochortus )  is  edible  and  has 
furnished  food  for  travelers  and  generally  eaten  by  the  Indians. 
The  wild  onion  is  no  doubt  a  harmless  plant.  Early  in  the  season 
death  camas  looks  like  grass.  It  starts  a  little  earlier  than  grass, 
and  being  more  succulent  and  devoid  of  disagreeable  odor  or 
taste,  is  eaten  freely. 

Wher  e  Found.  The  plant  is  found  growing  in  every  county 
in  the  mountain  districts  of  the  State.  It  is  not  found  in  the  east¬ 
ern  plains  district.  Its  favoiite  habitat  is  along  shallow  ravines 
where  theie  is  slight  seepage.  It  is  often  seen,  however,  growing 
singly  and  widely  scattered  over  the  high  mesas  and  in  shallow  de¬ 
pressions  commonly  found  in  such  places.  It  is  not  nearly  so 
abundant  nor  so  widely  distributed  as  larkspur.  The  camas  is  much 
more  abundant  in  the  northern  part  of  the  State. 

While  the  loss  from  camas  is  no  doubt  small  as  compared  with 
larkspur,  yet  for  several  reasons  it  is  to  be  looked  upon  as  one  of 
our  most  dangerous  poison  weeds.  Stock  on  the  range  are  usually 
thin  in  the  spring  and  ravenously  hungry  for  the  first  green  for¬ 
age  that  appears.  Camas  starts  a  little  ahead  of  grass  and  is 
relished  by  all  kinds  of  range  stock.  All  parts  of  the  plant  are 
extremely  poisonous  and  an  animal  does’  not  need  to  eat  a  large 
quantity  to  become  fatally  poisoned. 

In  Bulletin  No.  37,  of  the  Idaho  Experiment  Station,  is  found 
the  following ; 

“During  the  past  year  the  tops  were  found  by  the  Agricultural  De¬ 
partment  at  Washington  to  contain  a  poisonous  substance,  one  of  the 
powerful  veratrine  alkaloids.  The  bulbs  which  have  been  reputed  poison¬ 
ous  were  not  examined.  A  study  of  this  part  of  the  plant  in  the  Chemical 
Laboratory  of  the  Idaho  Experiment  Station  showed  the  presence  of  at 
least  three  alkaloids  similar  to  veratrine,  the  most  important  of  which 
appeared  to  be  related  to  violent  poison  hellebore,  a  single  milligram,  which 
is  only  one-fiftieth  of  a  grain,  killed  a  frog  in  two  minutes.  The  dose  of 
strychnine  fatal  to  the  frog  is  twice  that  amount,  from  which  some  idea 
of  the  intensely  poisonous  nature  of  the  bulbs  may  be  gathered.” 

Symptoms.  The  symptoms  of  poisoning  by  camas  are 
characteristic.  At  first  they  appear  to  be  excited,  are  unsteady 


20 


BURRETIN  1 13. 


in  their  movements,  breathe  rapidly,  stagger,  and  fall.  They  ap¬ 
pear  to  be  completely  paralyzed,  but  in  full  possession  of  their 
senses.  Spasms  come  on  more  or  less  severe  according  to  the 
amount  eaten.  In  mild  cases  .only  a  slight  stiffness  of  muscles  is 
noticeable,  and  this  soon  disappears.  In  severe  cases  of  poisoning 
the  animal  will  lie  flat  on  its  side,  unable  to  even  raise  the  head, 
and  death  will  be  delayed  for  several  hours. 

Treatment.  Chesnut  and  Wilcox  experimented  with  several 
antidotes,  among  the  most  promising  of  which  was  potassium  per¬ 
manganate,  given  by  the  mouth,  and  strychnine,  atropine,  mor¬ 
phine,  and  caffeine,  hypodermically.  In  their  first  report 
the  potassium  permanganate  is  found  to  be  a  valuable  physiologi¬ 
cal  antidote.  The  strychnine  and  atropine  had  little  if  any  curative 
value.  In  further  experiments  with  the  active  principle,  these 
authors  recommended  caffeine  diuretin. 

The  directions  for  giving  the  potassium  permanganate  as  an 
antidote  will  be  found  in  connection  with  the  treatment  for  poison¬ 
ing  by  larkspur. 

water  hEmrock.  ( Cicuta  occidentals ,  Greene.) 

Other  names:  Wyoming  water  hemlock;  cowbane;  spotted 
cowbone;  wild  parsnip;  snake  weed;  spotted  parsley;  death  of 
man,  etc. 

Description.  This  plant  is  more  commonly  spoken  of  in  Col¬ 
orado  as  wild  parsnip,  and  is  confused  with  at  least  three  other 
species,  which  it  greatly  resembles  on  account  of  the  similarity  in 
the  umbrellalike  expansion  of  the  top. 

It  is  often  mistaken  for  the  cultivated  parsnip,  which  it  re¬ 
resembles  to  some  extent.  It  is  not,  as  many  have  supposed,  the 
cultivated  parsnip  gone  wild.  On  the  contrary,  it  is  a  distinct 
species  and  can  be  distinguished  from  the  garden  species  by  having 
a  white  flower.  It  arises  from  a  bunch  of  thick  tuber  like  roots, 
which  when  cut  and  pressed  will  yield  a  gummy  secretion  which  con¬ 
tains  the  active  poison.  The  seeds  also  contain  the  poison  and  the 
foliage  early  in  the  season. 

Where  Found.  This  plant  abounds  throughout  the  entire 
Rocky  Mountain  region.  It  is  found  in  wet  or  swampy  places, 
along  streams,  on  ditch  banks,  and  often  invading  the  meadows. 
It  is  found  growing  on  the  plains  east  of  the  mountains,  more 
sparingly  but  under  similar  conditions. 

Symptoms.  There  is  manifest  symptoms  of  great  pain ;  the 
animal  performing  much  the  same  as  when  suffering  from  colic. 
This  is  followed  by  frenzy  and  spasms.  The  breathing  is  labored. 
There  is  frothing  at  the  mouth  and  finally  unconsciousness,  the 


PLATE  V. 

Wyoming  Water  Hemlock 
( Cicuta  Occidental  is.) 


PLATE  VI. 
Lupine 

(Lupinus  sericeus.) 


PLATE  VII. 
Aconite. 

( Aconitum  columbianum.) 


PLATE  VIII. 
Rubber  Plant 
( Hymenoxys  floribundu.) 


Larkspur  and  Other  Poisonous  Peants. 


21 


animal  dying  in  violent  convulsions.  In  bad  cases  of  poisoning  the 
animal  may  die  in  fifteen  minutes.  In  milder  cases  it  may  live  for 
several  hours  or  even  days  with  symptoms  less  pronounced. 

Treatment.  The  decomposed  state  of  the  bowels  after  death 
indicate  that  it  is  a  violent,  irritant  poison.  The  remedy  most 
available  and  effective  to  counteract  this  condition  is  melted  lard, 
or  linseed  oil,  morphine  in  three  grain  doses  hypodermically,  or 
laudanum  in  ounce  doses  to  relieve  pain  are  indicated.  Chloral 
hydrate  for  the  same  purpose  has  been  recommended,  but  being 
itself  very  irritating*  should  not  be  used. 

rupines.  ( Tnpinus ) 

Other  names  :  Wild  pea,  wild  bean,  blue  bean. 

There  are  several  species  of  the  lupine,  but  they  resemble  one 
another  so  closely,  that  a  person  knowing  one  will  have  no  difficulty 
in  recognizing  the  others. 

They  belong  to  the  pea  family  the  same  as  the  loco  weeds,  and 
the  two  have  often  been  confused.  The  different  species  of  lupine 
are  found  growing  extensively  in  the  central  and  western  half  of  the 
State,  by  the  road  side,  in  the  meadows,  and  on  the  mountain  side. 
It  is  generally  eaten  throughout  the  season  by  all  kinds  of  range 
animals  and  is  cut  extensively  for  hay.  The  poison  is  confined  en¬ 
tirely  to  the  seeds.  It  blooms  about  June  ist  at  an  altitude  of  6,000 
feet.  Most  of  the  cases  of  poisoning  observed  in  this  State  have 
been  in  sheep  and  from  eating  lupine  seeds  in  hay.  When  the  pods 
become  ripe  most  of  the  seeds  fall  to  the  ground  and  the  lupine 
hay  may  be  fed  with  safety,  and  it  makes  a  valuable  forage  crop. 
It  is  when  the  plants  are  cut  a  little  green  or  during  damp  weather 
and  the  seeds  are  retained  in  the  pods  in  large  quantities  that 
trouble  occurs. 

Symptoms.  The  symptoms  are  characteristic.  In  chronic 
poisining  ( lupinosis )  there  is  a  yellow  appearance  of  the  skin  and 
mucous  membranes.  The  urine  is  highly  colored  or  bloody,  de¬ 
praved  appetite,  clammy  mouth,  and  general  appearance  of  un¬ 
thriftiness.  This  chronic  condition  has  been  seen  in  horses  of  this 
State  more  than  in  other  animals. 

Sheep  are  very  fond  of  the  seeds,  and  where  they  are  accessible, 
eat  them  in  large  quantities,  producing  the  disease  in  the  acute  form. 
In  the  acute  poisoning  the  animal  rushes  about  in  different  direc¬ 
tions  in  a  state  of  frenzy.  It  finally  falls  in  a  fit,  has  violent  spasms 
and  dies,  usually  inside  of  two  hours. 

Treatment.  In  severe  cases  the  violent  symptoms  come  on 
so  rapidly  that  it  seems  all  but  useless  to  try  to  save  them.  In  less 
violent  cases  of  poisoning  melted  lard,  bacon  grease,  or  linseed  oil 


22 


Bulletin  113. 


are  usually  obtainable  and  might  be  given  to  advantage.  Laud¬ 
anum  or  morphine  to  counteract  the  nervous  condition.  Potassium 
permanganate  as  recommended  for  poisoning  by  larkspur  promises 
the  best  results,  but  must  be  given  early. 

the:  rubber  prant.  ( Hymenoxys  Moribund  a ,  (Gray)  Cockerell. 

During  the  summer  and  fall  of  1895  severe  losses  among  sheep 
were  reported  from  Middle  Park  on  account  of  this  plant.  It 
can  not  be  considered  as  a  truly  poisonous  plant  for  as  far  as  we 
know  it  contains  no  active  poisonous  principle.  When  eaten  in 
large  quantities,  however,  it  forms  an  indigestible  rubbery  mass, 
which  obstructs  the  bowels. 

POISONING  BY  ARKAIyl. 

Because  of  lack  of  salt  or  great  thirst,  concentrated  alkali 
water  is  often  drank  in  large  quantities,  and  with  fatal  results, 
especially  by  cattle.  The  symptoms  are  bloat,  frothing  at  the  mouth, 
and  scours.  Animals  poisoned  from  either  weeds  or  alkali  are 
commonly  found  adjacent  to  water  holes.  This  fact  combined 
with  the  similarity  of  symptoms,  makes  it  difficult  or  wellnigh 
impossible  for  the  ordinary  observer  to  determine  the  cause  with 
certainty.  Prevention  would  consist  in  salting  the  stock  regularly, 
and  being  careful  when  they  are  first  turned  on  the  range  to  see 
that  they  do  not  have  access  to  alkali  water  holes  until  they  have 
become  accustomed  to  the  dilute  form  of  the  salts.  Treatment 
would  consist  in  tapping  them  through  the  left  side  with  trocar 
or  knife  in  case  they  become  excessively  bloated.  Opium,  oak 
bark,  tannin,  and  aromatic  sulphuric  acid  are  indicated. 


Larkspur  and  Othe;r  Poisonous  Plants.  2 

Synopsis  of  Symptoms  and  Treatment  for  Poison  Weeds. 


CATTLE. 

Poisoned  on  Mountain  Ranges. — Bloat,  stiffness  of  legs,  continuous  swal¬ 
lowing,  twitching  of  muscles,  shallow  breathing;  in  April,  May,  or  June, — 
Larkspur. 

Treatment. — Puncturing  rumen  when  bloated;  potassium  per  inangan- 
ate  by  drench;  atrophin'e  hypodermically;  stimulants  of  whiskey,  ammonia, 
camphor. 

Poisoned  in  a  Field  of  Stunted  Growth,  of  Sorghum  or  Kaffir  Corn. — 

Bellowing,  staggering,  breath  has  odor  of  almonds,  suddden  death;  late 
in  summer, — Prussic  acid  from  eating  the  corn.  No  treatment. 

Poisoned  in  Low  Ground. — Convulsions,  frothing,  excessive  urination, 
not  many  affected  at  one  time;  in  the  early  spring  and  fall, — .Wild  parsnip. 

Treatment. — Melted  lard,  linseed  oil,  laudanum,  morphine. 

Poisoned  in  Alkali  Districts.^— Bloat,  diarrhoea,  frothing,  occurring 
usually  in  late  summer  or  fall, — Alkali. 

Treatment. — Tapping,  linseed  oil,  opium,  tannopine,  aromatic  sul¬ 
phuric  acid. 

Poisoned  in  Open  Range. — Emaciation,  unsteady  gait,  involuntary  rock¬ 
ing  of  the  head,  special  sense  disturbed,  crazy  when  disturbed, — Loco. 

Treatment. — Take  them  up  and  feed  grain. 

In  Mountain  Ranges. — Stumbling,  weaving,  stiffness  in  legs,  paralysis, 
do  not  lose  consciousness,  usually  a  number  affected, — Death  Camas. 

Treatment. — Potassium  permanganate  and  aluminum  sulfate  dissolved 
in  water. 

HORSES. 

In  the  Mountain  Ranges. — Violent  colic,  frenzy,  blindness,  spasms, 
bloody  urine;  in  the  late  summer  or  winter  months,  or  from  feeding  lupine 
hay  in  seed, — Lupines. 

Treatment. — Potassium  permanganate,  morphine,  melted  lard,  linseed 

oil. 

On  the  Farm. — Tardy  breathing,  fever,  stupor,  costiveness,  stumbling, 
head  pushed  against  wall,  or  hanging  on  manger, — Mouldy  hay,  fodder, 
potatoes,  carrots,  etc. 

Treatment. — Salicylic  acid,,  potassium  iodide,  creolin,  internally;  purga¬ 
tives. 

In  Alkali  Districts. — Bloating,  scouring,  frothing,  sweating, weakness; 
(Alkali). 

Treatment. — Tapping,  laudanum,  linseed  oil,  aromatic  sulphuric  acid, 
stimulants. 

In  low  Pastures  and  Along  Ditch  Banks. — Great  pain,  frothing,  frequent 
urination,  spasms;  occur  in  May  or  June,  or  in  fall  and  winter  when  roots 
of  hemlock  have  been  plowed  to  the  surface, — Water  Hemlock. 

Treatment. — Aloes,  morphine  in  large  doses,  potassium  permanganate, 
linseed  oil. 

SHEEP. 

Mountain  Ranges  in  August  or  Lupine  Hay  in  Winter. — Crazy,  running 
in  every  direction,  convulsions,  bloody  urine, — Lupines. 

Treatment. — Same  as  for  cattle. 

In  Mountain  Ranges. — Stiffness,  stumbling,  paralysis;  do  not  lose  con¬ 
sciousness;  many  affected;  occurs  in  April,  May,  and  June, — Death  Camas. 

Treatment. — The  same  as  for  cattle. 

In  Mountain  Ranges. — ‘Bloating,  stiffness  of  front  legs,  convulsions, 
shallow  breathing, — Larkspur. 

Treatment. — Same  as  for  cattle. 


24 


Bulletin  113. 


Some  Useful  References. 


Blankinship,  J.  W.  Poisonous  Plants  of  Montana.  Proc.  5th  An.  Sess. 
Pacific  N.  W.  Woolgrowers’  Assoc,  pp.  49-54.  1902. 

Brodie,  D.  A.  A  preliminary  report  of  poison  parsnip  in  western  Wash¬ 
ington.  Wash.  Exp.  Sta.  Bull.  No.  45,  pp.5-12.  1901. 

Chesnut,  V.  K.  Some  common  poisonous  plants.  Yearbook  U.  S.  Dept. 
Agric.  1896,  pp.  137-146. 

Chesnut,  V.  K.  Thirty  poisonous  plants  of  the  United  States.  U.  S.  Dept. 

Agric.,  Farmers’  Bull.  No.  86,  pp.  3-32.  1898. 

Chestnut,  V.  K.  Principal  poisonous  plants  of  the  United  States.  U.  S. 

Dept.  Agric.,  Div.  Bot.  Bull.  No.  20,  pp.  1-60.  1898. 

Chesnut,  V.  K.  Preliminary  catalog  of  plants  poisonous  to  stock.  15th 
An.  Rep.  Bureau  Animal  Ind.  1898,  pp.  387-420. 

Chesnut,  V.  K.  Some  poisonous  plants  of  the  northern  stock  ranges.  Year¬ 
book  U.  S.  Dept.  Agric.  1900,  pp.  305-324. 

Chesnut,  V.  K.  and  E.  V.  Wilcox.  The  stock  poisoning  plants  of  Montana. 
U.  S.  Dept.  Agric.,  Div.  Bot.  Bull.  No.  26,  pp.  1-150.  1901. 

Hedrick,  U.  P.  A  plant  that  poisons  cattle,  Cicuta.  Ore.  Exp.  Sta.  Bull. 
No.  46,  pp.  3-12.  1897. 

Hillman,  F.  H.  A  dangerous  range  plant  (Zygadenus).  Nev.  Exp.  Sta. 

'Newspaper  Bull.  No.  5.  (1893.)  No.  21,  (1897). 

Ladd,  S.  F.  A  case  of  poisoning — water  hemlock.  N.  Dak.  Exp.  Sta.  Bull. 
No.  35,  pp.  307-310.  1899. 

Ladd,  S.  F.  Water  hemlock  poisoning.  Ibid.  No.  44,  pp.  563-569.  1900. 

Morse,  F.  W.  q,nd  C.  D.  Howard.  Poisonous  properties  of  wild  cherry 
leaves.  N.  H.  Exp.  Sta.  Bull.  No.  56,  pp.  112-123. 

Nelson,  B.  S.  Feeding  wild  plants  to  sheep.  U.  S.  Dept.  Agric.,  Bureau 
Animal  Ind.  15th  An.  Rep.,  pp.  421-425.  1898.  Ibid.  Bull.  No.  22, 

pp.  10-14.  1898. 

Pammel,  L.  H.  Poisoning  from  cowbane  (Cicuta  maculata,  L.)  Iowa 
Exp.  Sta.  Bull.  No.  28,  pp.  215-228.  1895. 

Rich,  F.  A.  and  L.  R.  Jones.  A  poisonous  plant — the  common  horse-tail 
(Equisetum  arvense).  Vt.  Exp.  Sta.  Bull.  No.  95,  pp.  187-192.  1902. 

Slade,  H.  B.  iSome  conditions  of  stock  poisoning  in  Idaho.  Idaho  Exp. 
Sta.  Bull.  No.  37,  pp.  159-190.  1903. 

Vasey,  George.  Plants  poisonous  to  cattle  in  California.  Rep.  U.  S.  Dept. 
Agric.  1874,  pp.  159-160. 

Wilcox,  E.  V.  Larkspur  poisoning  of  sheep.  Mont.  Exp.  Sta.  Bull.  No.  15, 
pp.  37-51.  1897. 

Wilcox,  E.  V.  Lupines  as  plants  poisonous  to  stock,  etc.  Montana  Exp. 
Sta.  Bull.  No.  22,  pp.  37-53.  1899. 

Williams,  T.  A.  Some  plants  injurious  to  stock.  S.  Dak.  Exp.  Sta.  Bull. 
No.  33,  pp.  21-44.  1893. 

Willing,  T.  N.  Poisonous  plants.  Dept.  Agric.,  N.  W.  Ter.  (Regina). 
Bull.  No.  2  (1900)  and  No.  3  (1901),  pp.  27,  28. 


Bulletin  114 


May,  1906 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College. 


Insects  and  Insecticides. 


- BY 


C.  P.  GILLETTE 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
Fort  Collins,  Coloraio. 

1906. 


The  Agricultural  Experiment  Station. 

FORT  COLLINS,  COLORADO 


THE  STATE  BOARD  OF  AGRICULTURE 


Hon.  P.  F.  SHARP,  President . Denver . 

Hon.  HARLAN  THOMAS . Denver . 

Hon.  JAMES  L.  CHATFIELD . Gypsum.... 

Hon.  B.  U.  DYE . Rocky  Ford 

Hon.  B.  F.  ROCKAFELLOW . Canon  City. 

Hon.  EUGENE  H.  GRUBB . Carbondale. 


Hon.  A.  A.  EDWARDS . Fort  Collins 

Hon.  R.  W.  CORWIN . Pueblo . 


Governor  JESSE  F.  MCDONALD,  )  ~  . 

President  BARTON  O.  AYLESWORTH,  $  ex'°JJlC10 


TERM 

EXPIRES 

....1907 
....1907 
....1909 
. . . .  1909 
....1911 
....1911 
....1913 
....1913 


A.  M.  HAWLEY,  Secretary  EDGAR  AVERY  Treasurer 


Executive  Committee  in  Charge 

P.  F.  SHARP,  Chairman.  B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS 


STATION  STAFF 

L.  G.  CARPENTER,  M.  S.,  Director . Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S . Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D . : . Chemist 

W.  PADDOCK,  M.  S . Horticulturist 

W.  L.  CARLYLE,  M.  S . Agriculturist 

G.  H.  GLOVER,  B.  S.,  D.  V.  M . Veterinarian 

W.  H.  OLIN,  M.  S., . Agronomist 

R.  E.  TRIMBLE,  B.  S . Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S . . . .Assistant  Chemist 

EARL  DOUGLASS,  M.  S . Assistant  Chemist 

S.  ARTHUR  JOHNSON,  M.  S .  .Assistant  Entomologist 

B.  O.  LONGYEAR,  B.  S .  Assistant  Horticulturist 

J.  A.  McLEAN,  A.  B.,  B.  S.  A . Animal  Husbandman 

E.  B.  HOUSE,  B.  S  . Assistant  Irrigation  Engineer 

F.  KNORR . Assistant  Agriculturist 

P.  K.  BLINN,  B.  S . Field  Agent,  Arkansas  Valley,  Rocky  Ford 

E.  R.  BENNETT,  B.  S . Potato  Investigations 

Western  Slope  Fruit  Investigations,  Grand  Junction: 

O.  B.  WHIPPLE,  B.  S . Field  Horticulturist 

ESTES  P.  TAYLOR,  B.  S . Fieli?  Entomologist 


OFFICERS 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L  G.  CARPENTER,  M.  S . Director 

A.  M.  HAWLEY . . . Secretary 

MARGARET  MURRAY . Stenographer  and  Clerk 


CONTENTS. 


INSECTS. 


Introductory  Note  . 

Insects  Injurious  to  the  Apple . 

Attacking  the  Fruit . . . 

Codling  Moth,  Carpocapsa  pomonella  Linn . 

Howard’s  Scale,  Aspidiotus  howardi  Ckl . 

Attacking  the  Foliage . 

Leaf-roller,  Archips  argyrospila  Walk . 

Fall  Web-worm,  Hyphantria  cunea  Dru . 

Tent  Caterpillar,  Malacosoma  fragilis  Stretch . 

Apple  Flea-beetle,  Haltica  sp . 

Brown  Mite,  Bryobia  sp . 

Apple  Plant-louse,  Aphis  pomi  Fabr . 

Scale  Insects  (mostly  on  bark) . 

Grasshoppers . 

Attacking  Trunk  and  Branches .  . . 

Buffalo  Tree-hoppers,  Ceresa  sp . 

Borers,  Flat-headed,  Crysobothris  femorata  Fabr - 

Borers,  Twig,  Amphicerus  bicaudatus  Say . 

San  Jose  Scale,  Aspidiotus  perniciosus  Comst . . 

Putnam’s  Scale,  Aspidiotus  ancylus  Putnam . 

Howard’s  Scale,  Aspidiotus  howardi . 

Scurvy  Bark-louse,  Chionapsis  furfura  Fitch  . 

Woolly  Aphis,  Schizoneura  lanigera  Hausm . 

Oyster-shell  Bark-louse,  Lepidosaphes  ulmi  Bousche 

Attacking  the  Roots  . 

Woolly  Aphis,  Schizoneura  lanigera  Hausm . 

Insects  Attacking  the  Pear  . . . 

Pear-tree  Slug  Eriocampoides  limacina  Peck . 

Pear  leaf-blister,  Phytoptus  pyri . 

Howard’s  Scale,  Aspidiotus  howardi  Cockerell . 

Insects  Injurious  to  the  Plum . 

Attacking  the  Fruit . 

Plum  Gouger,  Coccotorus  prunicida  Walsh . 

Plum  Curculio,  Conotrachelus  nenuphar  Herbst . 

Attacking  the  Foliage . 

Fruit-tree  Leaf-roller,  Archips  argyrospila  Walk . 

Slugs,  Eriocampoides  limacina  Peck . 

Brown  Mite,  Bryobia  sp . 

Plant-lice,  several  species . 

Attacking  Trunk  and  Branches . 

Peach  Borer,  Sanninoidea  exitiosa  Say . 

Flat-headed  Borer,  Chrysobothris  femorata  Fabr . 

Scale  Insects,  several  species . 

Insects  Injurious  to  the  Cherry . 

Several  species  referred  to. 

Insects  Injurious  to  the  Peach . 

Peach  Twig-borer,  Anarsia  lineatella  Zell . 

Peach  Borer,  Sanninoidea  exitiosa  Say . 

Plant-lice . 

Insects  Injurious  to  the  Grape . 

Achemon  Sphinx,  Pholus  achemon  Drury . 

Eight-spotted  Forester,  Alypia  octomaculata  Fabr  .. 

Stem  Borer,  Amphicerus  bicaudatus  Say . 

Tree  Cricketts,  CEcanthus  sp . .  . 

Cottony  Scale;  Pulvinaria  innumerabilis  Rath . 

Grape  Flea-beetle,  Graptodera  chalybea  II 1 . 


PAGE 

5 

6 

6 

6 

6,  14 

7 

7,  17 

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8 
8 

8,  18 

8 

11 

11 

12 

13 

13 

12 

13 

13 

6,  14 

14 
14,  15 

15 
13 

14,  15 

15 

16 
16 

14,  16 
17 
17 
17 
17 

17 

7,  17 
16,  18 

8,  18 

18 
18 
18 
18 
18 

18 

18 

18 

21 

21 

22 

22 

22 

22 

22 

22 

23 


Grape-Leaf-hoppers,  Typhlocyba  sp .  23 

Grasshoppers .  23 

Insects  Injurious  to  Currants  and  Gooseberries .  23 

Imported  Currant-borer,  Sesia  tipuliformis  Clerk  . .  23 

Currant  Saw-fly,  Pristiphora  grossularise  Walsh .  23 

Currant  and  Gooseberry,  fruit  maggot . . .  24 

Currant  and  Gooseberry,  fruit  worm .  25 

Insects  Injurious  to  the  Strawberry .  26 

Strawberry  Leaf-roller,  Ancylis  comptana .  26 

Strawberry  Crown-borer,  Tyloderma  fragarise  Riley .  27 


INSECTICIDES. 


Preparation  and  Use .  28 

Substances  that  Kill  by  Being  Eaten .  28 

1.  White  Arsenic .  28 

2.  Arsenic  Bran-mash .  29 

3.  Paris  Green . 29 

4.  Scheele’s  Green  (Green  Arsenoid) .  .  31 

5.  Arsenate  of  Lead .  31 

6.  Arsenite  of  Lime .  32 

7.  London  Purple .  33 

8.  Bordeaux  Mixture .  33 

9.  White  Hellebore .  34 

10.  Borax . 34 

Substances  that  Kill  by  External  Contact .  34 

11.  Soap .  34 

12.  Whale-oil  Soap  . , .  35 

13.  Fish-oil  Soap  .  35 

14.  Kerosene  Emulsion .  35 

15.  Kerosene-milk  Emulsion .  36 

16.  Kerosene  and  Crude  Petroleum .  36 

17.  Gasoline .  37 

18.  Turpentine .  37 

19.  Lye  and  Washing  Soda .  37 

20.  Lime .  37 

21.  Lime,  Salt  and  Sulphur  Wash  .  37 

22.  Pyrethrum  or  Buhach . 38 

23.  Tobacco .  38 

24.  Sulfur  .  39 

24.  Hot  Water . 39 

Substances  that  Kill  by  Being  Inhaled .  39 

25.  Carbon  Bisulfide-“Fuma” .  39 

26.  Hydrocyanic  Acid  Gas .  40 

Substances  that  Repel .  41 

27.  Naphthaline,  Gum-camphor  and  Moth-balls .  41 

28.  Tobacco . 41 

29.  Ashes  .  41 

30.  Lime,  Plaster  and  Road  Dust .  42 

Insect  Traps . 42 

31.  Lights . 42 

32.  Sweetened  Water,  Cider,  Vinegar,  Etc .  42 

33.  Bandages  .  42 

34.  Hopper-dozers  or  Hopper-pans .  43 

35.  Sticky  Substances .  43 

The  Application  of  Insecticides .  43 

In  the  Dry  Way .  44 

In  the  Wet  Way .  44 

Pumps .  44 

How  to  Spray  .  46 

Nozzles  to  use . ' .  46 

Manufacturers  of  spraying  machinery .  47 


% 


INSECTS  AND  INSECTICIDES 


By  C.  P.  Gillette. 


The  present  bulletin  is  issued  to  supply  the  constant  call  for 
information  in  regard  to  the  common  insect  pests  and  the  rem¬ 
edies  that  are  commonly  used  for  their  destruction  or  prevention. 
It  is  really  Bulletin  71  revised  and  somewhat  enlarged.  The  most 
important  additions  are  the  short  articles  upon  two  Currant  and 
Gooseberry  insects,  the  Currant  and  Gooseberry  fruit  maggot  and 
the  Currant  and  Gooseberry  fruit  worm.  The  most  important 
omissions  are  in  cuts  of  spraying  apparatus. 

No  attempt  has  been  made  to  include  all  of  the  insects  in¬ 
jurious  to  fruits  in  the  State,  nor  to  give  the  methods  of  preparing 
all  the  insecticides  of  importance.  The  station  will  be  glad  to  re¬ 
ceive  inquiries  concerning  any  other  insect  pests  that  may  be 
troublesome  in  any  manner  to  residents  of  Colorado.  Always 
send  specimens  of  the  insects  and  their  injuries  when  possible  and 
give  as  much  information  in  regard  to  habits  and  injuries  as  you 
can.  Fuller  information  in  regard  to  any  insect  mentioned  in  this 
bulletin  will  also  be  given  upon  request. 

In  the  second  part  of  this  bulletin  the  insecticides  mentioned 
are  numbered,  so  that  in  the  first  part,  which  treats  of  injurious 
insects,  the  remedies  recommended  in  each  case  are  referred  to  by 
number  for  the  sake  of  brevity. 

Many  remedies  that  are  rarely  of  importance  and  other  sup¬ 
posed  remedies  that  are  of  little  or  no  use,  are  left  out  of  this  bul¬ 
letin.  The  attempt  is  to  give  the  more  important  remedies  for 
use  in  this  State. 


6 


THE  COLORADO  EXPERIMENT  STATION 


PART  I. 

INSECTS  INJURIOUS  TO  THE  APPLE. 

ATTACKING  THE  FRUIT. 

* 

CODLING  MOTH. 

Flesh-colored  larvae  eating  into  the  fruit  and  causing  wormy 
apples.  The  first  brood  of  larvae  (worms)  begin  eating  into  the 
fruit  when  early  apples  are  about  an  inch  in  diameter.  This  brood 
is  not  very  numerous  but  it  developes  into  a  second  brood  that 
comes  on  late  in  the  summer  which  is  very  much  more  numerous. 
The  moth  and  its  eggs  are  shown  at  Plate  I.,  Figs.  3  and  4. 

Remedies— The  arsenical  poisons  are,  by  far,  the  best  remedies  we 
have  for  this  insect.  See  remedies  3,  4,  5,  6,  7,  8. 

The  combination  of  Bordeaux  mixture  (8)  with  the  arsenites  is  very 
popular  farther  east  where  fungus  diseases  are  prevalent. 

Make  the  first  application  as  soon  as  the  blossoms  have  faded  and 
nearly  all  fallen.  Continue  the  application  till  every  calyx  (blossom) 
is  filled  with  the  liquid.  Repeat  the  application  in  one  week.  Or,  if  you 
were  very  thorough  in  the  first  treatment  and  if  no  blossoms  have 
opened  since,  it  will  probably  be  better  to  follow  the  plan  of  Mr.  Art. 
Roberts,  of  Paonia,  and  make  the  second  application  thirty  days  after 
the  first,  and  then  make  a  third  application  after  another  thirty  days. 
Whether  or  not  a  large  number  of  applications  are  needed  will  depend 
upon  the  number  of  wormy  apples  that  appear  during  July  and  August. 
If  heavy  showers  follow  a  treatment,  it  is  usually  well  to  repeat  the 
application.  This  is  not  so  necessary  if  arsenate  of  lead  is  used. 

Upon  the  thoroughness  of  the  first  and  second  applications  the  suc¬ 
cess  will  chiefly  depend.  Just  what  degree  of  benefit  may  be  expected 
from  later  applications  has  not  been  thoroughly  determined.  *Professor 
Cordley,  of  Oregon,  seems  to  have  proven  that  late  spraying  is  very  im¬ 
portant  in  that  state. 

Bandages  (36)  are  also  of  considerable  service  if  carefully  attended 
to,  and  if  the  worms  are  very  numerous.  Lights  to  trap  the  moths  are 
valueless.  Screen  cellar  windows  and  doors  where  fruit  is  kept. 

Plate  2,  Fig.  1,  shows  blossoms  from  which  the  petals  have 
fallen  and  also  small  apples  with  their  blossoms  (calyces)  tightly 
closed  so  that  little  or  no  spray  could  be  forced  into  them,  all  upon 
a  single  spur  of  a  Duchess  tree  at  one  time.  The  blossoms  at  (a) 
are  in  just  the  right  condition  to  receive  and  hold  the  poison.  The 
two  apples  should  have  received  the  spray  a  full  week  earlier.  In 
such  a  case  two  early  sprays  are  needed. 

HOWARD’S  SCALE  (Aspidiotus  How ardi) . 

This  scale  is  occasionally  found  upon  apples  in  Colorado.  It  closely 
resembles  the  San  Jose  scale  but  seldom  causes  the  red  blotch  where  it 
rests  upon  the  fruit.  Fig.  6  of  Plate  I.  shows  this  scale  upon  pear. 

For  remedies  see  San  Jose  scale  on  a  following  page. 


*Bull.  69;  Or.  Exp.  Station. 


INSECTS  AND  INSECTICIDES 


7 


ATTACKING  THE  FOLIAGE. 

LEAF-ROLLERS. 

The  fruit  tree  leaf-roller  (. Archips  argyrospila )  is  a  green  larva 
with  a  black  head  and  measures  about  three-fourths  of  an  inch 
in  length  when  fully  grown.  The  larvae  begin  to  hatch  with  the 
opening  of  the  buds  of  the  apple  trees  in  the  spring.  They  attack 
at  once  the  tenderest  leaves  and  fold  them  about  themselves  for 
protection.  When  abundant  they  may  completely  defoliate  the 
trees.  They  disappear  during  June  and  do  not  appear  again  until 
the  following  spring.  In  the  meantime  the'  eggs  may  be  found  in 
little  gray  patches  anywhere  upon  the  bark  of  trunk  or  limbs. 
See  Plate  I.,  Fig.  5. 

Remedies. — Crush  as  many  as  possible  of  the  egg  patches  during 
winter  and  early  spring.  The  best  remedy  is  to  spray  thoroughly  with 
one  of  the  arsenites  3,  4,  5,  6,  8,  as  soon  as  the  first  leaves  are  out.  Re¬ 
peat  in  one  week.  Make  a  third  application  in  another  week  or  ten  days 
if  it  seems  necessary. 

Protect  the  toads  and  insectiverous  birds,  as  both  feed  freely  upon 
the  rollers.  The  blackbirds  are  especially  destructive  to  them. 

FALL  WEB  WORM  | (Hyphantria  cunea) 

This  insect  is  often  mistaken  for  the  next  species.  The  webs 


Fig.  1.— Fall  Web-worm:  a  and  6,  caterpillars ;  c,  chrysalis;  d,  moth. 
(Howard,  Yearbook,  U.  S.  Dept,  of  Agriculture,  1895.) 


8 


THE  COLORADO  EXPERIMENT  STATION 


are  larger  and  loose  or  open  and  the  caterpillars  stay  in  them  to 
feed.  When  the  leaves  within  the  tent  are  devoured,  the  web  is 
extended  so  as  to  take  in  more  foliage.  These  tents  also  appear 
later  in  the  season  than  those  of  the  following  species.  They 
will  seldom  be  noticed  before  the  middle  of  July.  The  adult  in¬ 
sect  is  a  white  moth,  sometimes  speckled  with  black.  See  Fig.  i. 

Remedies.. — The  same  as  for  the  following  species  except  that  it  is  not 
practical  to  collect  the  eggs  which  are  deposited  upon  the  leaves. 

TENT  CATERPILLAR.  ( Malacosoma  fragilis.) 

This  insect  also  hatches  as  soon  as  the  leaf  buds  open,  and 
builds  small  webs  in  the  forks  of  the  branches.  A  large  number 
of  caterpillars  inhabit  a  web  or  tent,  which  is  increased  as  necessity 
requires.  See  Plate  I.,  Fig  i. 

Remedies. — While  the  foliage  is  off,  collect  the  large  egg-clusters 
which  are  stuck  to  small  limbs.  They  are  covered  with  a  dark,  spongy 
material  and  are  quite  readily  seen,  appearing  as  galls  or  swellings  of 
the  limbs.  If  this  remedy  has  been  neglected,  spray  with  the  arsenical 
mixtures  (3,  4,  5,  6  8).  While  the  tents  are  small  they  may  be  cut  out 
and  burned  if  on  small  limbs.  If  on  large  limbs  they  may  be  burned  out 
with  a  torch. 


APPLE  FLEA-BEETLE.  ( Haltica  sp.) 

The  apple  flea-beetle  is  a  small  inetalic-green  insect,  about  an 
eighth  of  an  inch  in  length,  which  jumps  or  drops  from  the  foliage 
when  disturbed.  It  is  most  abundant  on  young  trees  or  nursery 
stock  or  sprouts. 

Remedies  —  Any  of  the  arsenical  mixtures  (3  to  8]  are  effectual  in  de¬ 
stroying  this  insect  or  driving  it  from  the  foliage.  It  can  usually  be 
driven  from  the  leaves  by  the  application  of  dry  substances,  such  as 
lime,  ashes,  plaster,  etc.,  (30,  31). 

BROWN  MITE.  ( Bryobia  sp.) 

The  brown  or  clover  mite  is  extremely  small  and  its  presence 
is  usually  first  detected  by  the  faded,  sickly  appearance  of  the 
foliage.  See  Plate  III.,  PAig.  i.  The  trees  appear  to  need  more 
water.  The  mites  feed  upon  the  leaves  but  deposit  their  red  eggs 
upon  trunk  and  limbs.  When  very  abundant,  these  eggs  color  the 
bark  red,  which  is  most  often  noticed  during  winter. 

Remedies  —To  destroy  the  eggs  while  the  trees  are  dormant  (during 
winter)  use  lime,  salt  and  sulfur  mixture  (21);  kerosene  emulsion  (14), 
quadruple  strength;  whale-oil  soap  (12),  quadruple  strength,  or  crude 
petroleum  (16).  To  kill  the  mites  during  summer  use  kerosene  emulsion 
or  whale-oil  soap  of  ordinary  strengths.  It  is  far  better  to  treat  the  eggs. 

APPLE  PLANT  LOUSE.  ( Aphis  pomi .) 

A  green  louse  curling  the  leaves  of  apple  trees,  most  abundant 


INSECTS  AND  INSECTICIDES 


9 


PLATE  I. 


Fig.  1— Western  Tent-caterpillar:  A,  female  moth;  B,  O,  males.  D,  apple  twig  with 
egg  masses  (M).  F,  cocoon.  3,  egg-mass  of  American  Tent-caterpillar.  Life  size. 

Fig.  2— Cottony  Maple  scale:  A,  scales  mostly  hidden  by  secretion.  Life  size. 

Fig.  3— Codling  moth:  A,  wings  closed ;  B,  open.  Enlarged  about  I. 

Fig.  4— Apple  showing  white  egg  of  Codling  Moth  (under  letter  F).  Life  size. 

Fig.  5— Fruit  tree  leaf  roller:  A,  moth,  wings  open;  B,  closed.  C,  D,  egg  patches, 
hatched.  All  life  size. 

Fig.  6— Pear  with  Howard’s  Scale.  The  young  appear  as  minute  white  specks.  Life 
size.  Figures  from  photos  by  the  author. 


IO 


The  COLORADO  EXPERIMENT  STATION 


Fig.  1— Moths  of  Peach  Borer. 


Fig.  2— Peach  tree  bandaged  with  paper. 


Fig.  3— Peach  tree  with  wire  screen. 
All  after  Slingerland,  (Bull.  176,  Cor 
nell  Expt.  Station,) 


PLATE  4 


INSECTS  AND  INSECTICIDES 


late  in  the  season,  after  the  middle  of  July.  See  eggs  on  apple 
twig,  Plate  3,  Fig.  4.  These  are  minute  black  objects. 

Remedies. — For  the  destruction  of  the  eggs,  proceed  as  for  the  de¬ 
struction  of  the  eggs  of  the  brown  mite  above.  To  destroy  the  lice,  apply 
kerosene  emulsion  (14),  or  whale-oil  soap  (12),  thoroughly  and  in  a  man¬ 
ner  to  bring  the  liquid  in  contact  with  the  bodies  of  the  lice. 


SCALE  INSECTS. 

For  the  treatment  of  scale  insects  it  is  advisable,  in  each  case, 
to  write  to  the  Experiment  Station  for  specific  direction.  Specimens 
of  the  scale  should  also  be  sent.  Otherwise,  use  the  treatment  rec¬ 
ommended  for  San  Jose  scale — on  page  13. 


GRASSHOPPERS. 

Several  species.  Those  that  fly  from  tree  to  tree  can  probably 
be  managed  best  by  means  of  arsenical  sprays  (3  to  8),  when  safe 
to  use  them. 

Those  that  crawl  up  the  trunks  into  the  trees  and  jump  to  the 
ground  when  disturbed,  can  quite  largely  be  kept  out  of  the  trees 
by  the  use  of  arsenic  bran-mash  (2)  used  freely  about  the  border  of 


Fig.  2.— Hopper-dozer  or  Hopper-pan.  (After  Riley.) 

the  orchard,  and  by  sticky  bands  (35)  of  Raupenleim,  tree  tangle¬ 
foot,  printer’s  ink,  or  even  cotton  batting,  about  the  trunks  of  the 
trees.  If  the  sticky  bands  are  used  they  should  be  spread  upon 
strips  of  cardboard  which  have  first  been  wrapped  about  the  trunks. 


12 


THE  COLORADO  EXPERIMENT  STATION 


Fig.  3.— Rocky  Mountain  Locust,  laying  eggs  in  the 
ground;  a,  a,  females  with  their  abdomens  in  the 
ground;  6,  an  egg-pod  broken  open;  c,  scattered 
eggs;  d,  egg-packet  in  the  ground.  fAfter  Riley.) 


Grasshoppers  that 
injure  orchards  usually 
come  from  adjoining 
alfalfa  or  grass  fields.  In 

such  cases  the  free  use 
of  the  hopper  pan  (34) 
in  the  alfalfa  or  grass 
field  is  the  best  remedy. 
One  of  the  hopper-pans 
is  shown  at  Fig.  2.  *At 
Fig.  3  female  grasshop¬ 
pers  are  shown  in  the 
act  of  depositing  eggs 
in  the  ground. 


ATTACKING  TRUNK  AND  BRANCHES. 

APPLE  TWIG-BORER  ( Amphicerus  bicaudatus) 

A  cylindrical,  mahogany-colored  beetle,  about  one-third  of  an 
inch  long,  boring  holes  in  twigs  of  apple,  pear,  cherry  and  other 
trees  and  grapevines.  See  Fig.  4. 


Fig  4.— Apple  Twig-borer;  a,  beetle  dorsal  view;  a beetle  side  view;  b,  pupa  from 
beneath;  c,  grub,  side  view;  d,  apple  twig  showing  burrow;  e,  burrow  in 
tamerisk  with  pupa  at  bottom;  /,  stem  of  grape  showing  burrow.  All  enlarged 
except  stems  showing  burrows.  (Marlatt,  Farmer’s  Bulletin  70,  Div.  Ent.,  U.  8. 
Dept,  of  Agr.) 

Remedy. — Cat  out  the  infested  stems  and  destroy  the  borers. _ 

*A  very  successful  hopper  pan  made  and  used  by  Mr.  P.  K.  Blinn  at 
Rocky  Ford  is  described  and  illustrated  in  bulletin  112  of  this  station. 


INSECTS  AND  INSECTICIDES 


J3 


BORERS,  PLAT-HEADED. 


( Chrysobothris  femorata) 


A  whitish  grub  boring  beneath 
the  bark  of  apple  and  other  trees 
and  peculiar  in  appearance  in 
seeming  to  have  a  greatly  en¬ 
larged  flat  head.  Fig.  5. 


Remedies-— Remove  with  a  pocket 
knife  whenever  found.  Protect  the 


south  side  of  the  trunks  of  the  trees 


BUFFALO  TREE-HOPPER.  ( Ceresa  sp.) 


Three-cornered,  greenish  to  brownish  insects,  about  a  third  of 
an  inch  in  length.  They  jump  when  disturbed  and  puncture  twigs 
of  trees  and  stems  of  plants  for  the  deposition  of  their  eggs.  From 
these  punctures  oval  scars  result.  See  Plate  3,  Fig.  3. 

Remedies. — Infested  twigs  may  be  pruned  away  and  burned  during 
winter  or  spring.  Probably  clean  culture  is  the  best  prevention.  Keep 
down  all  weeds  and  unnecessary  vegetation  in  and  about  the  orchard. 

SAN  JOSE  SCALE.  ( Aspidiotus  perniciosus .) 

This  insect  is  very  easily  overlooked  and  may  be  present  in 
sufficient  numbers  to  kill  trees  before  its  presence  is  discovered  by 
the  orchardist.  They  may  infest  trunk,  twig,  fruit,  or  foliage. 
The  scale  is  nearly  circular,  about  one-sixteenth  of  an  inch  in  diam¬ 
eter,  dark  gray  in  color  with  a  darker  spot  at  the  center.  Anyone 
finding  such  scales  upon  any  tree  should  send  examples  at  once  to 
the  Experiment  Station  for  examination,  as  there  are  several  spe¬ 
cies  closely  resembling  each  other  in  outward  appearance.  As  yet 
this  scale  is  unknown  in  Colorado  orchards.  See  Plate  I.,  Fig.  6, 
which  shows  a  closely  related  species  on  pear. 

Remedies. —  Spray  with  lime  and  sulfur  mixture  (21)  while  the  trees 
are  dormant.  Or,  spray  with  whale-oil  soap  (12)  in  the  proportion  of  two 
pounds  to  a  gallon  of  water,  or  with  crude  petroleum  (16)  during  winter. 
If  trees  are  very  badly  infested,  it  will  often  be  best  to  cut  and  burn  them. 


PUTNAM’S  SCALE.  ( Aspidiotus  ancylus .) 


Very  closely  resembling  the  preceding  species.  Central  spot 
on  the  scale  reddish.  Remedies  the  same. 


i4 


THE  COLORADO  EXPERIMENT  STATION 


HOWARD’S  SCALE.  ( Aspidiotus  howardi.) 

This  scale  can  hardly  be  distinguished,  in  external  appearance,  from 
the  preceding  species.  It  is  the  only  scale  that  seems  to  be  at  all  com¬ 
mon  in  Colorado  orchards.  The  central  nipple  is  orange  red  and  the 
scales  are  often  quite  light  colored.  Its  presence  should  be  promptly  re¬ 
ported  to  the  Experiment  Station.  Remedies  the  same  as  for  San  Jose 
scale  above. 

SCURVY  BARK-LOUSE. 

( Chionaspis  fur  fur  a.) 

Small  white  scales  resem¬ 
bling  scurf  or  dandruff  on  the 
trunk  or  branches.  There  are 
two  sizes;  the  females  are 
larger  and  oval,  and  the  males 
are  very  small  and  slender. 
See  Fig.  6. 

Remedies  the  same  as  for 
the  San  Tose  scale. 

Fig  R.— Scurvy  Bark-louse;  a,  twig  showing  J 

scales  of  female  louse;  b,  twig  showing  scales 
of  male  louse;  c,  scale  of  female  greatly  en¬ 
larged;  d,  scale  of  male  greatly  enlarged. 

[Howard,  Yearbook,  U.  S.  Dep  of  Agr.,  1894.] 

WOOLLY  APHIS  ( Schizoneura  lanigera .) 

Small  dark  lice  more  or  less  densely  covered  with  a  white 
flocculent  secretion.  If  the  lice  are  crushed  in  the  hand  they  leave 
a  red  stain.  The  lice  attack  chiefly  tender  bark  about  wounds  or 
on  tender  growing  shoots. 


Fig.  7.— Woolly  Aphis,  root  form:  a, 
small  root  showing  swellings  caused 
by  the  lice;  b,  wingless  louse  show¬ 
ing  woolly  secretion;  c,  winged 
louse.  (After  Saunders.) 


Remedies.  — Early  in  the  sea¬ 
son,  when'  the  white  patches 
begin  to  appear  on  trunk  and 
branches,  paint  them  over  with 
pure  kerosene  (16),  crude  petro¬ 
leum,  or  a  very  strong  kero¬ 
sene  emulsion  (14),  or  whale- 
oil  soap  (12)  mixture.  If  the 
lice  become  abundant  late  in 
the  season,  apply  kerosene 
emulsion  or  whale-oil  soap  in 
ordinary  strength  but  with  a 
great  deal  of  force  and  a  coarse 
spray  in  order  to  wet  through 
the  waxy  secretion  which 
covers  them. 


This  insect  also  attacks  the  roots.  See  Fig.  7. 


INSECTS  AND  INSECTICIDES 


*5 


4 

OYSTER-SHELL  BARK-LOUSE.  ( Lepidosaphes  ulmi.) 

Scales  of  the  same  color  as  the  bark  of  the  tree,  about  one- 
eighth  of  an  inch  long,  curved  and  small  at  one  end.  Very  easily 
overlooked.  See  Fig  8. 

_  Remedies  the  same  as  for  the  San  Jose  scale. 


Fig.  8.— Oyster-shell  Bark-louse:  a,  female  scale  from  below,  showing  eggs, 
greatly  enlarged;  b,  the  same  from  above;  c,  female  scale  on  twig,  natural 
size;  a,  male  scale  enlarged.  [Howard,  Yearbook,  U.  S.  Dep.  of  Agr.,  J 894.] 

ATTACKING  THE  ROOTS. 

WOOLLY  APHIS.  ( Schizoneura  lanigera.) 

This  insect  attacks  the  roots  as  well  as  the  trunk  and  branches. 
It  causes  warty  excrescences  and  often  the  destruction  of  the 
greater  portion  of  the  smaller  roots.  (Fig.  7).  The  description 
of  the  louse  is  the  same  as  for  the  trunk  form  mentioned  above. 

Remedies. — Remove  the  earth  about  the  crown  for  a  distance  of 
about  two  feet,  put  in  four  to  six  pounds  of  tobacco  dust  (or  double  this 
amount  of  stems)  and  cover  again;  then  irrigate.  If  tobacco  can  not  be 
procured,  use  kerosene  emulsion  (14)  or  whale-oil  soap  (12)  of  the  ordi¬ 
nary  strengths  in  its  place,  pouring  in  a  liberal  quantity. 


INSECTSIATTACKING  THE  PEAR. 


Any  of  the  insects  mentioned  above  as  attacking  the  apple 
may  be  found  attacking  the  pear,  except  the  woolly  plant-louse, 
and  the  same  remedies  should  be  employed. 


i6 


THE  COLORADO  EXPERIMENT  STATION 


» 

PEAR-TREE  SLUG.  ( Eriocampoides  limacina ) 


Slimy  dark-colored  larvae  with  the  head  end  much  the 

larger,  somewhat  resembling 
snails,  resting  upon  the  up¬ 
per  surface  of  the  leaves, 
which  they  skeletonize.  See 
Fig.  9.  Two  broods  each 
year. 

Remedies. —Apply  white  hel¬ 
lebore  (9)  or  any  of  the  arse¬ 
nical  mixtures  (3-8) ,  by  dusting 
or  by  spraying.  Freshly 
slacked  lime  (20) or  wood  ashes 
(29)  freeley  dusted  upon  the 
larvae  will  kill  most  of  them. 

This  is  an  easy  insect  to 
control  and  should  not  be 
allowed  to  continue  its  seri¬ 
ous  injuries  to  the  pear, 

Fig.  9.— Pear-tree  Slug:  a,  adult  fly;  6,  larva  fLic 

or  slug  with  f-limy  covering  removed;  c,  plum  and  CUerry  in  tills 

same  as  preceding  in  natural  condition;  d ,  fof  oc  dnincr 

leaves  showing  slugs  and  their  injuries.  State  as  it  na;>  uccn 

(Marlatt,  Circular  26,  Second  Series,  U.  S.  vear? 

Dep,  of  Agr.,  Div.  Entomology.)  Ine  PaSL  iew  yCcllb- 


PEAR  LEAF  BLISTER  ( Phytoptus  pyri) . 

Small  dark  spots  upon  the  leaves,  sometimes  very  abundant 
and  involving  the  greater  portion  of  the  surface.  The  diseased 
portion  is  thickened  also  and  at  first  is  green  like  the  rest  of  the 
leaf.  The  leaves  often  fall  prematurely. 


Fig.  10- Plum  Gouger:  a,  plum  pit 
showing  hole  for  exit  of  gouger;  6, 
gouger;  c,  side  view  of  head  of 
gouger  showing  beak  and  antenna. 
(Riley  &  Howard,  Insect  Life,  Vol. 
II.,  U.  S.  Dep.  of  Agr.,  Div.  of  En¬ 
tomology.) 


Remedies . — Spray  the  trees  while 
dormant  with  kerosene  emulsion  (14), 
treble  strength;  whale-oil  soap  (12), 
one  pound  to  two  gallons  of  water;  or 
with  lime  and  sulfur  mixture.  Gather 
and  burn  as  many  of  the  fallen  leaves 
as  possible. 

HOWARD’S  SCALE. 

( Aspidiotus  howardi.) 

This  scale  is  too  common  in 
Colorado  orchards.  It  is  a  close 
relative  of  the  pernicious,  or  San  Jose 
scale,  but  so  far,  has  been  most  com¬ 
mon  upon  plum  and  pear.  Pears,  or 
any  fruit  affected  with  scales/ should 
be  reported  promptly  to  the  Experi¬ 
ment  Station.  See  Plate  I.,  Fig.  6. 

Remedies.— The  same  as  for  San 
Jose  scale  mentioned  under  apple  in¬ 
sects. 


INSECTS  AND  INSECTICIDES 


!7 


INSECTS  INJURIOUS  TO  THE  PLUM. 

ATTACKING  THE  FRUIT. 

PLUM  GOUGER.  ( Coccotorus  prunicida.) 

A  small  but  rather  robust  snout-beetle  about  a  quarter  of  an 
inch  in  length;  color  a  leaden  gray  with  head  and  thorax  oeherous 
yellow;  wing  covers  smooth  without  prominent  humps  on  them. 
The  beetle  eats  pin-holes  in  the  growing  plums  in  which  it  lays  its 
eggs.  The  larva  or  grub  eats  into  the  pit  and  feeds  upon  the  kernel, 
and  later  eats  a  hole  out  through  both  pit  and  flesh  of  the  plum 
just  before  the  plum  matures  (Fig.  io).  The  only  insect  in  Colo¬ 
rado  injuring  the  fruit  of  the  plum  to  any  extent. 

Remedies.  Jar  the  trees  early  every  morning,  or  in  the  evening,  from 
the  time  the  blossoms  are  out  till  very  few  beetles  can  be  obtained,  catch¬ 
ing  them  on  a  sheet  spread  beneath.  It  only  takes  a  very  few  beetles 
to  do  a  great  amount  of  harm,  as  I  have  found  by  actual  count  that  a 
single  female  may  lay  as  many  as  450  eggs.*  Gathering  and  destroying 
fu-  s  .  n»  plums  during  the  early  part  of  July  would  nearly  exterminate 
this  insect.  Spraying  with  an  arsenical  poison  (3, 4,  5,  6, 7,  8)  once,  a  few 
days  before  the  trees  blossom,  and  once  or  twice  after,  will  give  con¬ 
siderable  protection.  Use  the  poisons  in  two-thirds  ordinary,  or  standard 
strengths.  Arsenate  of  lead  (5)  is  probably  the  safest  to  use  on  the 
foliage  of  the  plum. 

PLUM  CURCULIO.  ( Conotrachelus  nenuphar.) 

This  beetle  is  often  confused  with  the  preceding.  As  yet  it  has 
not  been  reported  in  Colorado.  It  is  liable  any  year  to  appear  in 
our  orchards  and  all  should  be  on  the  look  out  for  it  so  as  to  do  all 
possible  to  stamp  it  out  or  prevent  its  rapid  spread.  It  is  as  destruct¬ 
ive  to  the  European  varieties  of  plums  as  the  codling  moth  is  to 
apples.  The  beetle  is  brown  to  blackish  in  color,  is  about  one- 
fifth  of  an  inch  long,  and  has  two  prominent  humps  and  numer¬ 
ous  smaller  ones  upon  its  wing  covers.  The  beetle  makes  a  cres¬ 
cent  shaped  cut  in  the  flesh  of  the  fruit  where  an  egg  is  deposited 
and  the  grub  does  not  enter  the  pit  but  feeds  on  the  flesh  outside 
ofpt,  causing  the  fruit  to  fall. 

Remedies.— Jarring  and  spraying  as  in  case  of  the  preceding  species. 

Should  anyone  find  what  he  thinks  to  be  the  work  of  this  in¬ 
sect  in  an  orchard,  it  is  hoped  he  will  notify  the  Experiment  Sta¬ 
tion  at  once. 

ATTACKING  THE  FOLIAGE. 

FRUIT-TREE  LEAF-ROLLER.  ( Archips  argyrospila) 

See  under  apple  insects.  Use  the  poisons  only  two-thirds  as 


*Insect  Life,  III.,  p.  227. 


1 8  THE  COLORADO  EXPERIMENT  STATION 

strong  on  the  plum  as  on  the  apple.  Arsenate  of  lead  is  least 
likely  to  injure  the  foliage. 

SLUGS. 

Skeletonizing  the  upper  surface  of  the  leaves.  See  pear-tree 
slug.  Use  the  same  remedies. 

BROWN  MITE 

See  under  apple  insects.  Remedies  the  same. 

PLANT  LICE. 

Two  or  three  species  attack  the  foliage  of  the  plum  badly  in 
Colorado.  Remedies  the  same  as  for  apple  plant-louse. 

Other  insects  attacking  apple  foliage  may  be  found  on  plum, 
where  they  are  destroyed  by  the  same  treatment  in  either  case. 

ATTACKING  TRUNK  AND  BRANCHES. 

THE  PEACH  BORER  ( Scinninoidea  exitiosa.) 

This  insect  often  attacks  the  plum.  For  its  treatment  see 
peach  enemies. 

FLAT-HEADED  BORER. 

See  under  apple  enemies. 

SCALE  INSECTS. 

See  under  apple  enemies.  When  scales  are  found  it  will  be 
well  to  send  specimens  to  the  Experiment  Station  for  identifica¬ 
tion  and  advice.  Howards’s  scale  and  Putnam’s  scale  both  occur 
on  plum  in  the  State.  They  have  been  injuriously  abundant  in  a 
few  isolated  cases  only. 


INSECTS  INJURIOUS  TO  THE  CHERRY. 

The  insects  attacking  the  cherry  in  Colorado  are  the  Fruit- 
tree  Leaf-roller,  Tent  Caterpillar,  Fall  Web-worm,  Brown  Mite, 
Plant  Lice,  Scale  Insects,  Grasshoppers,  Flat-headed  Borer,  Twig 
Borer,  Buffalo  Tree-hoppers  and  Pear  Slug  mentioned  above. 


INSECTS  INJURIOUS  TO  THE  PEACH. 

PEACH  TWIG-BORER.  ( Anarsia  lineatella.) 

This  is  the  worst  insect  enemy  of  the  peach  in  Colorado  at  the 
present  time.  As  soon  as  the  buds  begin  to  open  in  the  spring,  a 
small  brownish  larva  with  a  black  head  eats  into  the  buds  and 


INSECTS  AND  INSECTICIDES 


1 9 


PLATE  2. 

1— Blossoms  from  which  the  petals  have  fallen  and  still  in  good  condition  to 
receive  the  spray.  Also  apples  with  calyces  closed. 

Fig.  2  -Spraying  scene  in  orchard  of  Mr.  Bergher,  Palisade,  Colo.  Photos  by  the 

fillf  rt  A  ^ 


( 


THE  COLORADO  EXPERIMENT  STATION 


PLATE  3. 


Fig.  1— Grape  leaf  showing  bleached,  appearance  due  to  grape-leaf  hopper. 
Fig.  2— Eight-spotted  Forester  (Alypia  8-maculata):  A,  moth;  B,  larva. 


( Typhlo - 
Nearly  life 


Fig.  8 — Appie  twigs  iniured  by  Buffalo  Tree-hopper  (Ceresa  sp.)  Life  size. 

Fig.  4 — Eggs  of  apple,  plant-louse  on  apple  twigs.  Natural  size.  Photos  by  author. 


INSECTS  AND  INSECTICIDES 


21 


destroys  them.  When  the  new  shoots  start,  the  borer  eats  into 
them  causing  them  to  wilt  and  die.  Many  of  the  second  brood  of 
this  borer  eat  into  the  peaches,  causing  a  gummy  exudation  and 
ruining  them  for  market.  The  larvae  that  appear  in  the  spring 
spent  their  winter  in  little  excavations  which  they  made  in  the 
fall  in  the  bark  of  the  trees.  See  Figs,  n  and  12. 

Remedies .  — E arly  in  the  spring,  just  before  the  buds  open,  spray  the 
trees  with  lime  and  sulfur  wash  (21).  Whale-oil  soap  (12)  in  the  propor¬ 
tion  of  a  pound  to  two  gallons  of  water.  Fish-oil  soap  (13)  diluted  once  with 
water,  or  kerosene  emulsion,  will  doubtless  do  the  work  nearly  or  quite 
as  well  as  the  lime,  sulfur  and  salt.  Many  of  the  larvae  may  be  caught 
under  bandages  (33)  used  as  for  the  codling  moth. 

Mr.  E.  P.  Taylor  has  had  excellent  success  with  arsenate  of 
lead  (5)  at  Palisade,  Colo.,  this  season. 


Fig.  11.— Peach  Twig-borer:  a.  twig  of 
peach  showing  little  masses  of  chewed 
bark  above  the  larval  burrows;  b,  the 
same  enlarged;  c,  larva  in  winter  bur¬ 
row,  enlarged;  d,  hibernating  larva 
greatly  enlarged.  (Marlatt,  Bulletin 
10,  N.  S.,U.  S.  Dept,  of  Agr.,  Div.  of 
Entomology.) 


Fig  12.— Peach  Twig  and  Borer:  a,  young 
shoot  wilting  from  attack  of  borer;  b, 
adult  larva  enlarged;  c,  chrysalis  en¬ 
larged;  d,  tail  end  of  chrysalis  showing 
hooks.  (Marlatt,  Bulletin  10,  N.  S.,  U.  S. 
Dep.  of  Agr.,  Div.  of  Entomology.) 


THE  PEACH  BORER. 

A  yellowish  white  borer  attaining  the  length  of  about  one 
inch,  boring  beneath  the  bark  of  the  lower  trunk,  crown  and 
larger  roots.  See  Plate  4. 

Remedies. — Carefully  inspect  the  trees  every  fall  and  spring,  remove 
some  of  the  earth  next  the  crown,  and  search  for  and  remove  the  borers 
with  the  aid  of  a  pocket  knife.  Their  presence  is  usually  indicated  by 
the  exhudation  of  a  gummy  material  upon  the  bark.  Shields  of  stout 
paper  or  wire  screen  placed  about  the  trunks  and  left  therefrom  the  1st  of 
June  till  the  1st  of  August  will  serve  as  a  means  of  protection  from  egg- 
laying.  The  paper  screen  is  the  better.  (See  Plate  4,  Figs.  2  and  3.) 

PLANT  LICE. 

The  plant  lice  that  attack  the  foliage  of  the  peach  may  be 


22 


THE  COLORADO  EXPERIMENT  STATION 


treated  in  the  same  way  as  the  apple  plant-louse  mentioned  above. 
The  black  peach  aphis,  which  does  its  chief  injury  to  the  roots, 
should  be  handled  in  the  same  manner  as  the  woolly  aphis  of  the 
apple. 


INSECTS  INJURIOUS  TO  THE  GRAPE. 

THE  ACHEMON  SPHINX.  ( Pholus  achemon.) 

Hairless  caterpillars  devouring  the  leaves.  When  small,  each 
caterpillar  has  a  long  dorsal  spine  on  the  last  segment  of  the  body. 
When  nearly  grown,  the  spine  is  represented  by  a  shining  black 
spot.  These  larvae  resemble  the  large  tomato  “worm.” 

Remedies. — Any  of  the  arsenical  poisons  (3,  4,  5,  6,  7,  8)  may  be  used 
as  recommended  for  apple  leaf-rollers.  Pyrethrum  (24)  may  also  be  used 
as  powder  or  spray,  but  to  kill,  it  must  come  in  contact  with  the  cater¬ 
pillars.  Handpicking  is  the  best  remedy  in  a  small  vineyard. 

This  insect  is  also  bad  on  Virginia  creeper. 

THE  EIGHT-SPOTTED  FORESTER.  ( Alypia  octomaculata.) 

A  dark-colored  caterpillar,  about  one  and  one-half  inches  long 
when  fully  grown.  A  close  examination  will  reveal  numerous 
small  black  and  white  cross  lines  and  a  few  red  ones  to  each  body 
segment.  See  Plate  3,  Fig.  2. 

Remedies. — The  same  as  for  the  preceding  species. 

This  insect  also  infests  the  Virginia  creeper. 

STEM  BORER. 

See  apple  twig-borer,  which  also  attacks  the  grape. 

TREE  CRICKETS.  [ CEcanthus  sp.] 

The  female  cricket  punctures  stems  of  grape  and  other  plants 
and  in  each  puncture  deposits  a  long  cylindrical  egg.  The  punc¬ 
tures  are  usually  in  rows  lengthwise  of  the  stem  and  look  like 
needle  thrusts. 

Remedies.  Cut  out  badly  infested  stems.  Keep  the  vineyard  clean 
ot  all  weeds. 


COTTONA  SCALE.  [ Pulvinaria  innumerabilis .] 

This  scale,  commonly  found  infesting  soft  maple,  sometimes 
attacks  grapevines.  See  Plate  I.,  Fig.  2." 

Remedies . —Kero sene  emulsion  made  strong,  so  as  to  be  one-fifth  kero¬ 
sene,  thoroughly  sprayed  during  the  winter  or  early  spring  is  very  ef¬ 
fectual.  TV  hen  the  little  lice  first  hatch  from  the  scales,  about  the  last  of 
no?e’-nhS  °^dinafy  sprays  of  kerosene  emulsion  (14)  or  whale-oil  soap 
(12)  will  destroy  them.  If  the  spraying  is  delayed  till  a  heavy  scale  has 
formed  over  the  lice,  stronger  applications  will  be  required. 


INSECTS  AND  INSECTICIDES 


23 


GRAPE  FLEA  BEETLE.  ( Graptodera  chalybaea) 

A  small  steel-blue  beetle  appearing  early  in  the  spring  and 
again  in  midsummer  and  feeding  upon  the  foliage.  The  beetles 
deposit  eggs  which  soon  hatch  into  small  dark-colored  larvae 
which  also  eat  holes  in  the  leaves. 

Remedies  —  Arsenical  poisons  (3-8)  sprayed  or  dusted  upon  the  foliage. 
If  unsafe  to  use  poisons,  dust  freely  withPyrethum  (22). 

GR\PE-LEAF  HOPPERS.  (Typhlocyba  sp.) 

Small  jumping  and  flying  insects,  often  called  “grape  thrips.” 
The  insects  often  fly  out  from  the  vine  in  great  numbers  when  the 
latter  is  jarred  and  return  quickly  to  the  under  side  of  the  leaves. 
As  a  result  of  the  punctures  and  the  extraction  of  the  sap,  the 
leaves  lose  their  dark  green  color  and  at  first  are  minutely  specked 
and  freckled  with  white,  as  shown  at  Plate  3,  Fig.  I.  Fater  the 
leaves  shrivel  and  die.  The  red  spiders,  brown  mites  and  thrips 
cause  a  similar  appearance  of  the  foliage  they  attack. 

Remedies.— Spray  forcibly  with  kerosene  emulsion  (14), kerosene  and 
water  (16),  or  whale-oil  soap  (12)  very  early  in  the  morning  while  the  in¬ 
sects  are  dormant  and  drop  readily  from  the  leaves.  Burn  dry 
leaves,  dead  grass  and  other  rubbish  in  the  vicinity  of  the  vineyard 
during  winter  or  early  spring,  on  a  cold  day. 

GRASSHOPPERS. 

Remedies.— Use  arsenical  spray  (3  8)  where  safe.  If  not  safe  to  spray, 
use  the  arsenic-bran  mash  (2)  freely  about  the  borders  of  the  vineyard 
and  about  the  vines.  Make  free  use  of  hopper-pans  (34)  in  adjoining  fields 
to  reduce  the  number  of  hoppers  before  they  reach  the  vineyard.  Plow 
or  thoroughly  harrow  the  ditch  banks  and  the  borders  of  the  field  late  in 
the  fall  to  destroy  as  many  of  the  eggs  as  posible. 


INSECTS  INJURIOUS  TO  THE  CURRANT. 

IMPORTED  CURRANT-BORER.  [Sesia  tipuliformis .] 

Yellowish  white  larvae  burrowing  in  stems,  giving  rise  to 
wasp-like  moths  in  June.  The  moths  closely  resemble  those  of 
the  peach  borer,  shown  at  Plate  4>  Fig.  1. 

Remedies .  —  Cut  out  the  infested  stems  and  burn  them  during  winter 
or  early  spring.  Also  keep  the  old  wood  well  trimmed  out  of  the  bushes, 
and  always  burn  promptly  the  parts  cut  out. 

CURRANT  SAW-FLY.  [ Pristiphora  grossulariae.] 

A  green  larva,  about  half  an  inch  long  when  fully  grown, 
feeding  upon  the  leaves  of  currant  and  gooseberry  bushes.  Ap¬ 
pearing  late  in  June  and  again  about  the  last  of  August.  The 
adult  insect  is  a  black  four-winged  fly  about  the  size  of  a  house- 


1 


24 


THE  COLORADO  EXPERIMENT  STATION 


fly.  The  eggs  are  deposited,  one  in  a  place,  under  the  epidermis 
of  the  leaves. 

Remedies. — The  best  remedy  for  this  pest  is  white  hellebore  (9)  dusted 
lightly  over  the  foliage  in  the  evening.  If  this  is  carefully  done,  nearly 
every  larva  can  be  found  deadunder  the  bushes  next  morning.  Arsenical 
sprays  (3-8)  may  be  used  either  dry  or  in  water,  as  for  other  leaf-eating 
insects.  These  poisons  should  not  be  used  before  the  currants  are 
picked.  Pyrethrum  (22)  may  be  safely  used  at  any  time. 


THE  CURRANT  AND  GOOSEBERRY  FRUIT  MAGGOT 

( Epochra  canadensis). 

A  two-winged  fly  about  the  size  of  an  ordinary  house  fly,  but 
yellowish  brown  in  color  and  with  dusky  bands  across  the  wings, 
appears  among  the  bushes  when  the  berries  are  about  half  grown 
and  “stings”  the  fruit  with  its  sharp  ovipositor.  In  each  puncture 
an  egg  is  deposited  just  beneath  the  skin  as  shown  at  <?,  and  the 
punctured  spot  turns  dark  as  shown  at  #,  Fig.  14. 


Fig  13.— Adult  of  Curraan  tnd  Gooseberry  Fruit-maggot. 


The  eggs  soon  hatch  into  little  white  maggots  that  eat  into 
the  seeds  and  cause  the  berries  or  currants  to  turn  red  and  drop. 
When  fully  grown,  the  maggot  leaves  the  fruit  and  works  its  way 
beneath  the  surface  of  the  ground  where  it  stays  until  the  next 
summer  when  it  comes  forth  again  as  a  fly  to  lay  eggs  upon  the 
next  crop  of  gooseberries  and  currants. 

Remedies.— Insecticides  are  useless  here.  If  the  stung  fruit  could  be 
gathered  and  destroyed  everyday  or  two,  there  would  be  fewer  flies. 


INSECTS  AND  INSECTICIDES 


25 


another  year.  If  the  surface  of  the  ground  is  well  turned  under  during 
the  fall  or  early  spring,  many  of  the  insects  would  be  prevented  from 
emerging.  Thorough  cultivation  close  to  the  plants  throughout  the  sea¬ 
son  would  do  much  to  keep  this  insect  in  check. 


Fig.  14.— Currant  and  Gooseberry  Fruit-maggot:  A,  section  through  a  goose¬ 
berry  showing  egg  and  puncture  at  e ;  B,  two  gooseberries  on  a  stem 
showing  egg  puncture,  or  sting,  at  a.  Original.  Drawings  by  Miss  M.  A. 
Palmer. 

This  is  probably  our  worst  currant  and  gooseberry  pest  in 
Colorado,  and  as  it  also  attacks  the  wild  currants  and  gooseberries 
it  is  likely  always  to  be  rather  common  in  the  mountainous 
districts. 

THE  CURRANT  AND  GOOSEBERRY  FRUIT  WORM 

( Zophodia  bella  Hulst.) 

A  flesh-colored  worm,  looking  very  much  like  the  apple  worm 
and  about  two-thirds  of  an  inch  in  length  when  fully  grown  also 
attacks  the  gooseberries  and  currants  in  Colorado  and  often  de¬ 
stroys  a  very  large  proportion  of  the  fruit.  Leaves  and  fruit  are  loose¬ 
ly  webbed  together  by  the  worm  which  feeds  upon  the  berries. 
It  eats  a  hole  large  enough  to  enter  and  after  devouring  the 
whole  interior  of  one  berry  it  goes  to  another.  The  adult  insect 
is  a  gray  moth  with  rather  long  narrow  wings.  The  insect  and 
its  injuries  are  shown  in  Fig.  15. 

Remedies. — Poisonous  sprays  would  doubtless  kill  many  of  these 
worms  but  they  would  render  the  currants  and  gooseberries  unsafe  to 
be  used  as  food.  If  one  has  a  few  bushes  only  for  home  use,  the  worms 
could  be  nearly  all  destroyed  by  pinching  the  web  clusters  of  fruit  be¬ 
tween  the  thumb  and  finger  every  day  or  two  until  no  more  appeared. 
Thorough  cultivation  would  also  destroy  a  large  proportion  of  the  chrys¬ 
alids  that  spend  the  winter  near  the  surface  of  the  ground  about  the 
bushes. 


26 


THE  COLORADO  EXPERIMENT  STATION 


Fig  15. -Currant  and  Gooseberry  Fruit-worm:  A,  worm;  B,  moth;  C,  goose¬ 
berries  webbed  together.  Original.  Drawings  by  Miss  M.  A.  Palmer. 


INSECTS  INJURIOUS  TO  THE  STRAWBERRY. 


STRAWBERRY  LEAF-ROLLER.  [. Ancylis  comptana.] 


Fig  16.— Strawberry  Leaf-roller;  a,  larva, 
natural  size;  b,  head  end  of  larva  en¬ 
larged;  c,  moth  about  twice  natural  size; 
d ,  tail  end  of  larva  enlarged  (After 
Saunders.) 


Small  brownish  or  green¬ 
ish  larva  attaining  a  length  of 
nearly  half  an  inch  and  having 
the  habit  of  folding  the  leaves 
of  the  strawberry.  In  these 
folds  the  larva  lives  and  feeds 
and  finally  changes  to  a  small 
rust-colored  moth  with  white 
marking  on  the  wings.  See 
Figs.  16,  1 7. 


Remedies. — When  the  fruit  has  been  gathered,  scatter  straw  over  the 
vines  and  burn  it.  Arsenical  sprays  (3-8)  mav  be  used,  but  the  worms 
are  so  protected  in  the  folded  leaves  that  it  is  difficult  to  get  a  poisonous 
dose  to  them.  The  vines  will  put  up  a  good  growth  of  tops  after  the 
burning,  if  it  is  not  done  too  late. 


27 


INSECTS  AND  INSECTICIDES 


STRAW BE  RRY 
CROWN  BORER. 

[ Tyloderma  fragarise .] 

A  small  yellowish 
white  grub  boring  into 
the  crown  of  the  plant 
during  summer. 

Remedies. — B  urning 
as  for  the  preceding  spe¬ 
cies  will  destroy  a  large 
proportion  of  the  borers. 
Bo  not  allow  the  plants 
to  become  very  old,  but 
plow  each  year  or  once 
in  two  years  as  soon  as 
the  berries  are  picked, 
and  start  a  new  bed  at 
some  distance  from  the 
old  one.  Poisons  are  of 
doubtful  value. 


Fig.  17.— Strawberry  leaves  showing  their  ap¬ 
pearance  after  being  folded.  (After  Weed.) 


28 


THE  COLORADO  EXPERIMENT  STATION 


PART  II. 


INSECTICIDES. 

THEIR  PREPARATION  AND  USE. 

In  order  to  be  able  to  apply  insecticides  intelligently  and  with 
success,  it  is  important  to  understand  something  of  the  habits  of  the 
particular  insects  to  be  destroyed  and  also  of  the  nature  of  the  rem¬ 
edies  to  be  used.  Many  insects,  like  grasshoppers  and  the  potato 
beetle,  devour  the  surface  tissue  of  plants,  while  others,  like  plant- 
lice,  squash-bugs,  and  scale  insects  insert  sharp  tubular  beaks  into 
the  tissues  of  plants  and  suck  the  sap  from  beneath  the  surface. 
Insects  of  the  first  class  may  nearly  always  be  destroyed  by  means 
of  food-poisons,  such  as  arsenic,  Paris  green,  hellebore,  etc.,  while 
those  of  the  latter  class  are  unaffected  by  food  poisons  and  have  to 
be  killed  by  substances  that  come  in  contact  with  the  surface  of 
their  bodies,  or  in  some  other  manner.  It  is  not  necessary  to  be  a 
skilled  entomologist  in  order  to  determine  which  class  of  insects 
is  doing  injury  to  the  plants  in  question.  If  the  leaves  are  ragged  or 
eaten  full  of  holes,  it  is  practically  certain  that  the  injury  is  being 
done  by  an  insect  with  biting-mouth  parts.  If  the  leaves  simply 
wilt  and  dry  up  without  having  the  tissue  eaten  away,  the  insect 
doing  the  injury  is  of  the  second  type  mentioned.  The  most  com¬ 
mon  remedies  for  this  class  of  insects  are  kerosene  emulsion, 
whale-oil  soap,  crude  petroleum,  and  lime  salt  and  sulfur  washes. 

In  many  cases  it  is  impossible  to  get  an  insecticide  upon  the 
insect  that  it  is  desired  to  kill,  or  upon  its  food,  and  then  other 
means  have  to  be  used  to  prevent  the  injuries.  Borers,  under¬ 
ground  feeders  upon  roots,  and  weevils  living  in  seeds,  are  examples 
of  such  insects. 

In  the  pages  that  follow  I  shall  not  attempt  to  treat  of  all  the 
methods  used  to  destroy  insects  or  avoid  their  injuries,  but  the 
more  important  ones  only. 

SUBSTANCES  THAT  KILL  BY  BEING  EATEN. 

■m 

Nearly  all  the  food-poisons  have  for  their  active  principle 
arsenious  acid,  or  white  arsenic  (Ass03).  White  hellebore  and 
borax,  are  about  the  only  exceptions. 

1.  WHITE  ARSENIC. 

While  this  is  the  cheapest  of  the  arsenical  poisons,  it  is  used 
but  little,  except  for  the  purpose  of  making  arsenical  compounds 


INSECTS  AND  INSECTICIDES 


29 


with  other  substances.  Because  some  states  have  passed  laws  re¬ 
quiring  a  high  percentage  of  arsenic  in  Paris  green,  arsenic  has 
been  used  as  an  adulterant  of  this  poison,  and  thereby  working  an 
injury  to  the  purchaser  if  not  a  benefit  to  the  manufacturer  of  it, 
because  arsenic  is  much  cheaper  than  Paris  green;  and  when  it  is 
mixed  with  the  latter,  it  greatly  increases  its  liability  to  burn 
foliage.  The  reason  that  white  arsenic  burns  foliage  badly  is  it 
dissolves  in  water  and,  when  in  solution,  it  penetrates  the  leaves 
and  kills  the  living  tissue.  Arsenical  mixtures  must  never  be  in 
solution ,  but  only  in  suspension ,  in  the  water  that  is  used  to  dis¬ 
tribute  them  upon  foliage. 

2.  ARSENIC  BRAN-MASH. 

Prepared  by  mixing  one  pound  of  arsenic  and  20  to  50  pounds 
of  bran  together  with  just  water  enough  to  thoroughly  moisten  the 
mass.  Some  prefer  to  add  a  pound  of  sugar  to  the  above  in  order 
to  cause  the  particles  of  bran  to  adhere  to  each  other,  so  that  it  may 
be  distributed  in  little  balls  pressed  together  with  the  hands  or 
with  a  paddle.  This  poisoned  bran  is  used  for  the  destruction  of 
grasshoppers  in  orchards  and  vineyards  where  it  is  not  possible  to 
use  a  hopper-pan.  Many  prefer  to  sow  the  moistened  bran  and  ar¬ 
senic  broadcast  where  the  grasshoppers  are  numerous.  Paris 
green  may  be  substituted  for  the  arsenic. 

3.  PARIS  GREEN. 

This  poison  in  a  pure  state  is  said  to  be  composed  of  three  sub¬ 
stances — arsenious  acid,  acetic  acid,  and  copper  oxide — united  in 
a  chemical  combination.  The  percentage  of  arsenic  may  vary 
considerably,  as  these  substances  do  not  always  combine  in  exactly 
the  same  proportions.  The  range  is  nearly  always  between  55  and 
60  per  cent,  arsenic,  with  an  average  of  about  58  per  cent.  *Mr.  J.  K. 
Haywood,  one  of  the  chemists  in  the  Department  of  Agriculture 
at  Washington,  D.  C.,  says  that  the  chemical  composition  of  Paris 
green  should  be: 

Per  cent. 


Arsenious  acid . 58.65 

Copper  oxide . 31.29 

Acetic  acid  . 10.06 


Pure  Paris  green  is  one  of  the  very  best  of  the  arsenical  com¬ 
pounds  for  the  destruction  of  insects,  but  this  poison  is  often  found 
greatly  adulterated  upon  the  market.  If  adulteration  is  sus¬ 
pected,  or  if  the  poison  is  being  purchased  in  any  considerable 
quantity,  it  is  advisable  to  test  its  purity  in  some  way.  Pure  Paris 


*Farmer’s  Bull.  No.  146,  U.  S.  Dept,  of  Agr. 


30 


THE  COLORADO  EXPERIMENT  STATION 


green  is  entirely  soluble  in  ammonia,  giving  a  clear  blue  liquid.  If 
any  particles  can  be  seen  floating  through  the  liquid,  or  settling  to 
the  bottom,  the  article  is  not  pure.  If  the  amonia  dissolves  all, 
there  can  be  little  doubt  that  it  is  pure.  This  is  a  test  that  anyone 
can  make.  The  particles  of  Paris  green  are  entirely  bright  green 
in  color  and  globular  in  form,  and  the  presence  of  an  adulterant  can 
be  most  easily  detected  under  a  microscope  of  moderate  power. 
Prof.  Woodworth  of  the  University  of  California  explains  another 
method  by  which  impurities  can  usually  be  detected  in  Paris  green. 
It  is  by  placing  a  small  amount  of  the  poison  on  a  clean  piece  of 
glass  and  then  slanting  the  glass  and  jarring  it  so  as  to  cause  the 
powder  to  slide  to  the  lower  side.  If  this  is  done  carefully  the 
adulterants,  which  are  not  green  in  color,  will  fall  behind  and  can 
be  detected  with  the  unaided  eye. 

Where  there  are  several  persons  in  the  same  neighborhood 
wanting  this  poison,  it  is  best  for  all  to  order  together  and  then  send 
a  sample  to  a  chemist  for  analysis.  If  a  good  number  unite  in 
this  way  the  Station  chemist,  most  likely,  would  be  willing  to 
make  the  test  free. 

Application  op  Paris  Green  to  Plants . — This  poison  is  usually 
applied  in  a  watery  spray,  and  the  most  common  strength  is: 


Paris  green . 1  pound 

Water . . . 160  gallons 

Lump  lime  (freshly  slacked) . 2  pounds 


On  very  sensitive  foliage,  like  that  of  the  peach,  apricot,  nec¬ 
tarine  and  bean,  it  would  be  safer  to  use  200  gallons  of  water  to  a 
pound  of  poison.  A  pound  to  100  gallons  is  quite  safe  for  appli¬ 
cations  upon  apple,  cherry,  cabbage,  beets,  potatoes  and  most  other 
trees  and  plants  in  the  dry  atmosphere  of  Colorado.  The  poison 
always  should  be  placed  in  a  small  quantity  of  water  first  and 
thoroughly  stirred  in  and  then  poured  into  the  full  amount  of 
water  to  be  used. 

The  chief  objection  to  the  use  of  pure  Paris  green  as  an  insecti¬ 
cide  is  its  high  specific  gravity,  which  causes  it  to  settle  rapidly  in 
water.  Pumps  used  to  apply  this  poison  always  should  have  some 
means  of  keeping  the  water  well  stirred. 

Dry  applications  may  be  made  in  various  ways.  Sometimes 
the  poison  is  used  pure,  in  which  case  the  lightest  possible  dusting 
is  made  over  the  plants.  It  is  usually  better  to  dilute  the  poison 
with  about  twenty  times  its  own  weight  of  flour,  plaster  or  lime 
when  a  more  liberal  dusting  may  be  made.  This  method  is  more 


INSECTS  AND  INSECTICIDES  3 1 

economical  of  the  poison  and  enables  one  better  to  tell  when  all 
parts  of  the  plant  have  been  treated.  A  good  proportion  is: 

Paris  green . 1  pound 

Common  flour . . * . 25  pounds 

The  advantages  of  flour  over  lime  or  plaster  are,  it  helps  bet¬ 
ter  to  stick  the  poison  to  the  leaves  and  is  not  distasteful  to  insects. 
Particles  of  poison  imbedded  in  a  mass  of  plaster  or  lime  would 
probably  be  avoided  by  most  insects.  Filling  the  blossom  ends  of 
apples  with  lime  mixed  with  poison  may  drive  the  worms  to  eat 

their  way  into  the  apples  where  they  will  escape  the  poison 
entirely. 

The  methods  of  applying  dry  poisons  are  chiefly  two.  If  low 
plants,  like  cabbages  and  tomatoes,  are  to  be  treated,  and  the  area 
to  be  covered  is  not  too  great,  a  very  satisfactory  method  is  to  make 
a  small  sack — about  ten  inches  long  by  five  inches  in  diameter — 
of  strong  cheesecloth  or  other  light  muslin,  fill  half  full  with  the 
mixture  of  poison  and  flour  and  then  shake  or  jolt  the  sack  over 
the  plants. 

Where  large  areas  are  to  be  treated,  or  where  it  is  necessary  to 
make  the  application  to  trees  or  high  bushes,  some  kind  of  dust 
gun  or  bellows  is  an  advantage.  Powder  guns  of  different  kinds 
are  upon  the  market  and  some  of  them  are  being  extensively  ad¬ 
vertised  at  this  time.  These  instruments  have  a  place  to  fill,  but 
I  do  not  believe  they  can  take  the  place  of  the  watery  spray  for 
large  trees,  and  particularly  for  the  application  of  poisons  for  the 
destruction  of  the  codling  moth. 

4.  scheede’s  green  (green  arsenoid). 

Scheele’s  green,  also  sold  as  ugreen  arsenoid,’1  differs  very  little 
from  Paris  green  in  chemical  composition,  except  in  lacking  the 
acetic  acid.  It  is  considered  as  effectual  as  an  insect  destroyer,  and 
has  a  great  advantage  over  Paris  green  in  being  much  more  finely 
divided,  so  that  it  remains  in  suspension  in  water  for  a  much  longer 
time.  It  is  also  cheaper  in  price.  Dr.  Marlatt,  of  the  Division  of 
Entomology,  says  it  should  replace  Paris  green  as  an  insecticide. 

Apply  either  wet  or  dry,  as  recommended  for  Paris  green. 

5.  ARSENATE  OF  DEAD. 

This  compound  contains  only  about  20  to  25  per  cent,  of  ar¬ 
senic  acid,  but  has  some  important  advantages  over  the  other  arsen¬ 
ical  compounds.  It  is  so  completely  insoluble  in  water  that  it  may 
be  used  in  almost  any  strength  without  injuring  foliage  and  con¬ 
sequently  is.  least  likely  to  injure  plants  that  are  most  sensitive  to 
arsenical  poisons.  When  suspended  in  water  this  poison  is  so  finely 


32 


THE  COLORADO  EXPERIMENT  STATION 


divided  that  it  settles  slowly,  and  consequently  can  be  more  evenly 
distributed  than  most  arsenical  mixtures.  Its  third  point  of  su¬ 
periority  is  in  its  adhesive  qualities  when  applied  to  foliage.  Appli¬ 
cations  made  to  foliage  in  the  latter  part  of  May  at  this  Station  could 
plainly  be  seen  upon  the  leaves  the  first  of  September.  The  dis¬ 
advantage  of  the  poison  is  its  not  being  quite  so  quick  to  kill  the 
insects  that  eat  it  as  are  the  other  arsenites,  consequently  it  is 
necessary  to  use  it  in  stronger  mixtures. 

To  prepare  arsenate  of  lead,  dissolve  in  water  arsenate  of  soda 
and  acetate  of  lead  (white  sugar  of  lead)  in  the  portion  of  three 
pounds  of  the  former  to  seven  pounds  of  the  latter.  Then  use  not 
less  than  five  or  six  pounds  of  the  combined  chemicals  to  each 
hundred  gallons  of  water.  Three  or  four  times  this  strength  will 
do  no  harm  to  foliage.  If  the  poison  is  purchased  ready  made, 
use: 

Arsenate  of  lead . 4  to  6  pounds 

Water . 100  gallons 


6.  ARSENITE  OF  LIME. 

White  arsenic  and  lime  may  be  made  to  combine,  forming  an 
arsenite  of  lime  that  is  practically  insoluablein  water.  The  poison 
may  be  prepared  in  either  of  two  ways.  What  is  known  as  the 
Kedzie  formula  is  as  follows: 

“Boil  two  pounds  of  white  arsenic  and  eight  pounds 
of  salsoda  for  fifteen  minutes  in  two  gallons  of  water. 

Put  into  a  jug  and  label  * poison ’  and  lock  it  up. 

When  ready  to  spray,  slack  two  pounds  of  lime  and 
stir  it  into  forty  gallons  of  water,  adding  a  pint  of  the 
mixture  from  the  jug. 

The  other  method  is  to  boil  together  arsenic,  lime  and  water 
for  a  full  half  hour  in  the  following  proportions: 


White  arsenic . 1  pound 

Lump  lime . 4  pounds 

Water .  .  4  gallons 


Then  dilute  to  200  gallons  of  water  before  applying  to  foliage. 

These  preparations  have  become  very  popular  in  the  past  few 
years  and  deservedly  so.  White  arsenic  is  cheap  and  consequently" 
is  in  very  little  danger  of  adulteration,  so  that  one  is  almost  certain 
of  the  strength  of  his  mixture  when  using  this  poison.  Care  must 
be  taken,  however,  to  use  fresh  unslacked  lime  of  good  quality. 

Before  being  diluted  for  use,  the  mixture  should  be  passed 
through  a  coarse  cloth  or  seive,  to  take  out  the  lumps  that  would 
otherwise  clog  the  spraying  nozzle. 


INSECTS  AND  INSECTICIDES 


33 


7-  LONDON  PURPLE. 

London  purple  is  a  by-prodnct  in  the  manufacture  of  aniline 
dyes  and  has  for  its  active  principle  arsenite  of  lime.  It  also  con¬ 
tains  some  free  arsenic,  lime,  coloring  matter  and  other  impurities. 
The  amount  of  arsenic  present  is  subject  to  considerable  variation, 
but  will  usually  range  between  40  and  55  per  cent.  As  there  is 
often  considerable  soluble  arsenic  present,  it  is  always  best  to  use 
a  pound  or  two  of  freshly  slacked  lime  with  every  pound  of  the 
poison  if  used  in  water. 

This  poison  is  finely  divided  and  remains  in  suspension  in 
water  much  longer  than  Paris  green  does  and  it  usually  sells  at 
about  two  thirds  the  price  of  that  poison.  It  seems  to  be  going  into 
disfavor  because  of  its  variable  composition  and  the  danger  of  its 
burning  foliage.  It  is  also  considered  somewhat  less  effectual  in 
killing  insects  than  is  Paris  green  or  Scheele’s  green.  It  should 
compare  favorably,  however,  with  the  prepared  arsenite  of  lime  in 
its  power  to  kill  insects,  and  there  is  little  danger  that  it  will  be 
adulterated,  as  it  is  a  waste  product. 

Apply  either  wet  or  dry  in  the  manner  and  in  the  same  pro- 
pcrtions  as  are  previously  recommended  for  Pans  green  5  being  sure 
to  add  a  pound  or  two  of  freshly  slaked  lime  for  each  pound  of 
poison  if  used  as  a  spray. 


8.  BORDEAUX  MIXTURE  AND  THE  ARSENITES. 


Bordeaux  mixture  is  a  fungicide  and  is  the  substance  most 
often  used  for  the  destruction  of  fungous  diseases  that  attack 
the  surface  of  the  plants.  It  has  been  found  to  be  of  value  for 
use  against  flea-beetles,  and  the  writer  also  demonstrated  its 
value  a  number  of  years  ago  as  a  medium  in  which  to  spray  Paris 
green  or  London  purple.  These  poisons  can  be  used  very  strong 
in  this  mixture  without  injury  to  foliage  and  they  do  not  in  the 
least  lessen  its  effect  as  a  fungicide.  Such  a  mixture  will  destroy 
both  insects  and  fungi  with  one  application. 

Bordeaux  mixture  may  be  prepared  as  follows:  Take  of 


Copper  sulfate 
Quicklime  .... 
Water . 


4  pounds. 
4  pounds. 
45  gallons. 


Dissolve  the  copper  sulfate  in  a  gallon  of  hot  water,  slake  the 
lime  in  another  gallon  of  water,  and  then  add  the  milk  of  lime 
slowly  to  the  copper  sulfate  solution  while  the  latter  is  being  con¬ 
stantly  stirred.  Then  add  43  gallons  of  water. 

If  insects  are  to  be  killed  at  the  same  time,  add  to  the  above 
quantity  of  Bordeaux  mixture  one-third  pound  of  London  purple, 
Paris  green  or  Scheele’s  green,  or  two  pounds  of  arsenate  of  lead.  ’ 


34 


THE  COLORADO  EXPERIMENT  STATION 


9.  WHITE  HELLEBORE. 

Hellebore,  as  obtained  from  drug  stores,  is  a  light,  yellowish- 
brown  powder.  It  is  a  vegetable  poison  and  is  obtained  by  pulver¬ 
izing  the  roots  of  an  European  plant  Vercttrum  album.  It  is  not  as 
poisonous  as  the  arsenites  and  consequently  it  is  not  as  effective  in 
the  destruction  of  most  insects,  but  it  has  its  special  uses.  Slugs, 
which  are  the  young  of  saw-flies,  are  particularly  susceptible  to  its 
effects.  The  poisonous  property  is  an  alkaloid  and  it  loses  it  virtue 
after  being  exposed  to  the  air  for  a  few  days.  For  this  reason  it 
can  not  be  used  where  it  is  likely  to  remain  long  before  being 
eaten,  and  it  must  be  kept  in  tight  receptacles  and  must  not  be 
kept  too  long  before  using.  It  is  often  useful  for  the  destruction 
of  insects  upon  plants  containing  fruit  that  will  soon  be  used  for 
food. 

Dry  applications  are  easily  made  upon  low  plants  by  making  a 
small  cheesecloth  sack,  through  which  the  dust  may  be  sifted 
lightly  over  the  foliage.  The  best  tim  e  to  apply  is  in  the  evening 

I11  the  wet  way  use: 


White  hellebore . 1  ounce. 

Water . 3  gallons. 


Apply  as  a  spray  in  the  evening. 

10.  BORAX. 

Used  chiefly  for  the  destruction  of  cockroaches.  Spread  the 
powdered  borax  upon  bread,  sweet  potato  or  banana  peelings,  or 
mix  with  sweetened  chocolate,  and  place  the  bait  where  the 
cockroaches  can  get  at  it. 

SUBSTANCES  THAT  KILL  BY  EXTERNAL  CONTACT. 

Substances  in  this  group  are  chiefly  used  against  insects  that 
take  liquid  food  from  beneath  the  surface  of  the  plant  by  means  of 
a  tubular  rostrum  or  beak,  but  they  may  be  used  against  many 
other  soft-bodied  insects  with  success.  Insects  having  a  hard  outer 
crust  to  their  bodies  resist  these  substances  and  are  not  easily  killed 
by  them.  If  insects  are  covered  with  a  powdery  or  cottony  material, 
the  insecticide  will  have  to  be  applied  with  considerable  force  to 
cause  it  to  penetrate  to  the  body.  Applications  must  always  be 
thorough,  because  only  those  insects  will  be  killed  that  have  the 
substances  thrown  upon  them. 

II.  SOAP. 

The  ordinary  soft  soaps  and  laundry  soaps  have  long  been 
used  for  the  purpose  of  killing  vermin  on  plants  and  animals,  and 


INSECTS  AND  INSECTICIDES 


35 


they  have  considerable  insecticidal  value,  particularly  for  the  de- 
struction  of  very  tender  insects,  like  plant  lice.  The  scans  that 
are  specially  useful  for  the  destruction  of  insects,  are  sold  as^hale- 

isZXihoi rp’ or  tree-soaps-  whatever  the  name- 

12.  WHAEE-OIE  OR  TREE-SOAP. 

For  ordinary  plant  lice  one  pound  of  the  soap  to  eight  or  ten 

tghis°strenl7h  teriiS  Sll,*C-ent  if  the  aPPlicatio»  is  thorough.  Double 
this  strength  will  not  injure  most  plants  and  is  often  required  to 

destroy  more  resistent  insects.  For  scale  lice,  like  the  San  Jose 

scale  for  example,  it  is  used  as  strong  as  a  pound,  or  even  two 

pounds,  to  a  gallon  of  water.  These  strongest  applications  can 

mint  111  the  wlnter_or  early  sPring  when  the  trees  are  dor- 

ant.  The  soap  is  more  effectual  if  applied  when  quite  hot. 

13.  FISH-OIE  SOAP  (home-made). 

Lodeman  in  his  “Spraying  of  Plants”  gives  the  following  for¬ 
mula  for  the  preparation  of  fish-oil  soap: 

Potash  lye .  1 

Fish-oil  . ..."  , . . 1  P9und 

Soft  water .  . a  “  Plnts 

Dissolve  the  lye  in  boiling  water  and  then  add  the  oil  and  boil 
Tirs  longer  When  using  dissolve  a  pound  of  this  soap 
m  from  six  to  ten  gallons  of  water.  Use  for  the  same  purposes  as 
whale-oil  soap,  and  m  the  same  strengths.  1  1 

14  KEROSENE  EMUESION. 

cide  for  tberHPafrati7n  iS  ?r°bably  ,the  best  general  purpose  insecti- 
e  for  the  destruction  of  insects  by  external  contact.  The  mate¬ 
rials  composing  it  are  always  at  hand  and  it  is  not  difficult  to 

beTsed  fft6r  °nKihaS  rf?  afttle  exPerience.  Soft  water  should 

“break”’  t  firsS  A*  &  T**  is.,used  k  may  be  necessary  to 

break  it  first  by  adding  washing  soda  or  potash  lye. 

To  make  the  emulsion  use  the  ingredients  in  the  following 
proportions:  & 

Kerosene . . . o1  P?iUnc^ 

Water .  . ^a110ns 

^^Pare  by  dfssolvmg  the  soap  in  a  gallon  of  water,  then 
while  the  soapy  water  is  boiling  hot,  remove  from  the  fire  and 
mmediately  add  two  gallons  of  kerosene  and  agitate  briskly  for  a 
few  minutes.  If  a  large  amount  is  being  made,  use  a  force  pump- 
and  forcibly  pump  the  mixture  back  into  the  receptacle  that  com 


THE  COLORADO  EXPERIMENT  STATION 


36 

tains  it  until  all  is  a  frothy,  creamy  mass.  If  such  a  mixture  is  not 
obtained  in  a  very  few  minutes,  put  the  whole  over  the  fire  again 
until  it  boils  and  then  repeat  the  pumping,  and  the  emulsion  will 
almost  surely  form.  When  put  back  for  reheating,  watch  every 
moment  to  see  that  it  does  not  boil  over  and  take  fire .  This  work 
should  be  done  out  of  doors.  After  the  emulsion  is  made,  add  the 
remaining  27  gallons  of  water  and  all  is  ready  for  use. 

Small  quantities  may  be  emulsified  with  a  rotary  egg-beater. 

Whale-oil  soap,  or  any  cheap  soap,  may  be  used. 

Clean  dishes  and  clean  water  should  be  used.  Every  particle 
of  dirt  in  the  emulsion  serves  as  a  center  of  attraction  about  which 
the  oil  droplets  will  collect  and  then  rise  to  the  top  to  form  a  film 
of  oil  on  the  surface. 

The  strength  above  given  is  suitable  for  most  insects.  Most 
plant  lice  may  be  killed  with  an  emulsion  of  half  the  above 
strength. 

15.  KEROSENE-MIEK  EMULSION. 

Kerosene  will  emulsify  with  milk,  also,  and  when  small  quan¬ 
tities  are  wanted  it  is  often  less  trouble  to  use  the  milk  than  to 
prepare  the  soapy  water.  These  proportions  are: 

Milk  (sour) . -I  gallon 

Kerosene . 2  gallons 

Dilute  with  water  as  in  the  preceding  formula.  If  sweet  milk 
is  used,  add  a  little  vinegar.  Otherwise  it  may  be  impossible  to 
form  a  stable  emulsion. 

16.  KEROSENE  AND  CRUDE  PETROLEUM. 

These  oils  are  used  pure,  and  also  diluted  with  water,  for  the 
destruction  of  scale  and  other  insects.  Experiments  in  the  Eastern 
States  seem  to  indicate  that  the  safest  time  to  apply  .is  early  in  the 
spring,  just  before  the  buds  swell,  and  on  a  bright,  windy  day  when 
the  oil  will  evaporate  rapidly.  It  seems  that  when  applied  in 
moderation,  in  the  proportion  of  40  parts  of  the  oil  to  60  of  water, 
these  substances  will  -seldom  injure  apple,  cherry  or  pear  trees, 
but  can  hardly  be  applied  to  tenderer  trees,  such  as  peach  and 

plum,  without  further  dilution. 

When  diluted  with  water  in  the  form  of  a  spray  they  may  be 
used  upon  foliage  of  most  plants,  without  injury,  in  the  proportion 
of  one  of  the  oil  to  five  or  six  of  water.  Most  plant  lice  are  killed 
in  mixtures  as  weak  as  one  of  oil  to  fifteen  or  twenty  of  water. 

Pumps  are  now  made  for  the  purpose  of  mixing  the  oil  and 
water  in  the  form  of  a  spray,  and  so  do  away  with  the  need  of 
preparing  an  emulsion.  The  one  who  has  the  insecticides  to  appl) 


INSECTS  AND  INSECTICIDES 


37 

must  decide  whether  or  not  he  will  go  to  the  extra  trouble  of  mak¬ 
ing  the.  emulsion  or  whether  he  will  go  to  the  extra  expense  of 
purchasing  a  special  and  somewhat  more  costly  pump  that  may 

not  work  very  satisfactorily  at  all  times. 

«* 

17.  GASOLINE. 

This  oil  is  also  destructive  to  insect  life.  Its  chief  use  is  for 
the  destruction  of  bed-bugs.  It  is  applied  pure  by  means  of  an  oil¬ 
can  or  hand  atomizer.  To  be  effectual  the  bugs  must  be  thoroughly 
treated  with  it.  As  it  is  inflamable,  care  must  be  taken  not  to 
ring  ~re  near  until  the  apartments  where  it  is  used  are  well  aired. 

18.  TURPENTINE. 

Turpentine  is  used  for  the  same  purposes  as  gasoline  and  the 
same  precaution  applies. 

19.  EYE  AND  WASHING  SODA. 

^hese  substances  are  in  considerable  popular  favor  for  the 
destruction  of  insects,  but  the  writer’s  experience  with  them  has 
not  been  encouraging.  In  the  proportion  of  a  pound  to  three  gal- 
ons  of  water  they  may  be  used  upon  the  trunks  of  trees  and  will 
kill  soft-bodied  insects  that  might  be  wet  by  them.  To  be  used 
upon  foliage  they  should  be  diluted  to  a  pound  to  forty  gallons  of 
water,  and  in  this  strength  they  will  hardly  destroy  the  tenderest  of 
insects.  .  Kerosene  emulsion  or  whale-oil  soap  are  much  more  ef¬ 
fectual  insecticides. 


20.  DIME. 

Kime,  either  wet  or  dry,  may  be  used  freely  upon  foliage  with¬ 
out  fear  of  injury.  It  is  of  very  little  value  as  an  insecticide.  When 
freshly  slaked  and  freely  dusted  upon  the  slugs  that  infest  pear, 
cherry  and  plum  trees,  it  causes  them  to  drop  off  and  most 
of  these  perish.  Experiments  at  this  Station  have  not  been  wholly 
successful  in  killing  slugs  this  way.  As  a  coating  upon  the  bodies 
of  fruit  trees  it  undoubtedly  does  much  to  prevent  sun-scald  late  in 
winter  and  early  in  spring.  The  addition  of  a  liberal  amount  of 
skim-milk  or  salt,  or  both,  to  the  preparation  will  greatly  increase 
its  adhesive  qualities.  The  following  formula  is  printed  in  the 
1899  report  of  the  Canada  Experimental  Farm: 

Skim-milk .  6  gallons. 

W&ter . 30  gallons. 

. 60  pounds. 

katt . 10  pounds. 

21.  DIME,  SALT  AND  SULFUR  WASH. 

This  wash,  when  properly  made,  is  one  of  the  most  effectual 


38 


THE  COLORADO  EXPERIMENT  STATION 


applications  for  the  destruction  of  scale  insects  and  eggs  of  the 
brown  mite,  particularly  in  dry  climates,  like  that  of  Colorado.  It 
should  be  used  only  in  the  winter  or  spring,  while  the  trees  are 
dormant.  The  ingredients  may  be  in  the  following  proportions: 


Lump  lime  (good) . 20  pounds. 

Sulfur . 15  pounds. 

Salt . 10  pounds. 

Water . 50  gallons. 


Slake  the  lime,  preferably  with  hot  water,  in  an  iron  kettle  or 
a  barrel,  and  while  slaking,  slowly  add  the  sulfur  and  stir  it  in. 
Then  boil  over  a  good  fire  or  by  means  of  a  jet  of  steam  in  about 
one  half  the  required  amount  of  water  (25  gallons)  for  an  hour  or 
two,  or  until  a  dark  red  color  is  obtained.  Then  add  the  salt  and 
boil  for  15  minutes  longer,  strain,  dilute  to  50  gallons  and  apply 
while  hot.  Many  are  leaving  out  the  salt  and  they  seem  to  have 
just  as  good  results. 

22.  PYRETHRUM,  BUHACH,  OR  PERSIAN  INSECT  POWDER. 

This  substance  is  a  vegetable  powder  and  is  obtained  by  pul¬ 
verizing  the  dried  blossoms  of  plants  of  the  genus  Pyrethrum.  It 
may  be  obtained  at  almost  any  drug  store,  and  is  peculiar  in  its 
power  to  kill  insects  while  it  is  not  poisonous  to  the  higher  ani¬ 
mals.  It  may  be  used  either  wet  or  dry.  If  applied  in  water,  use 
in  the  proportion  of: 

Pyrethrum . 1  ounce. 

Water . 3  gallons. 

If  applied  dry,  use  pure  and  make  a  very  light  application,  or 
dilute  with  flour  and  apply  more  freely. 

If  thoroughly  disseminated  in  the  air  of  a  room  it  will  soon 
bring  to  the  floor  all  the  flies  and  mosquitoes  therein.  A  good  way 
to  rid  a  room  of  flies  is  to  make  a  thorough  dusting  of  the  powder 
through  the  room  and  then  close  the  room  tightly  for  the  night. 
Then  in  the  morning  sweep  up  the  flies  and  burn  them.  If  they 
are  not  destroyed  in  this  way  after  being  stupefied,  many  will  finally 
overcome  the  action  of  the  powder  and  live. 

23.  TOBACCO. 

Tobacco  has  long  been  used  in  one  way  or  another  for  the  de¬ 
struction  of  insects.  Its  chief  use  seems  to  be  for  the  destruction 
of  lice.  When  slowly  burnt  the  smoke  may  be  utilized  for  the 
destruction  of  lice  on  plants  in  greenhouses  or  window  gardens. 
In  the  form  of  a  fine  dust  it  is  often  effectual  in  ridding  plants  of 
flea-beetles,  and  in  the  form  of  dust  or  stems  is  probably  the  best 
remedy  we  have  for  woolly  aphis  on  the  roots  of  apple  trees. 

A  decoction  made  by  boiling  tobocco  dust  or  stems  in  water  in 


INSECTS  AND  INSECTICIDES 


39 


the  proportion  of  a  pound  to  three  or  four  gallons,  is  destructive  to 
plant  lice  (Aphidse)  and  to  lice  upon  cattle.  Tobacco,  very  finely 
powdered,  in  the  form  of  snuff,  may  also  be  used  dry  against  the 
same  insects.  It  is  best  to  first  spray  the  insects  with  water. 

24.  SULFUR. 

Everyone  knows  of  the  use  of  sulfur  fumes  for  the  destruction 
of  animal  life.  Sulfur  is  specially  destructive  to  ured  spiders”  and 
“brown  mites,”  and  may  be  applied  as  flowers  of  sulfur,  dry,  through 
a  blow-gun  of  some  sort,  or  mixed  in  soapy  water  or  soap  solutions 
in  the  proportion  of  an  ounce  to  a  gallon  of  the  liquid  and  applied 
as  a  spray.  The  liquid  must  be  kept  thoroughly  stirred,  as  the 
sulfur  settles  quickly. 

\ 

25.  HOT  WATER. 

Water  heated  to  130  to  140  degrees  Far.  kills  very  quickly 
any  insect  that  is  put  into  it,  but  is  harmless  to  plants  unless  they 
are  kept  submerged  for  a  long  time.  Lice,  especially  those  on 
roots,  may  often  be  killed  conveniently  with  hot  water. 

SUBSTANCES  THAT  KILL  BY  BEING  INHALED. 

There  are  two  insecticides  of  this  sort  that  are  of  special  im¬ 
portance.  As  both  are  destructive  to  vegetable  life  also,  care  must 
be  had  in  their  use  that  they  are  not  applied  in  strengths  that  will 
destroy  the  plants.  It  is  important  that  tents,  rooms,  or  other  re¬ 
ceptacles  in  which  objects  are  placed  for  fumigation,  be  as  nearly 
air  tight  as  possible. 

26.  CARBON  BISULFIDE;  UFUMA.” 

This  is  a  clear,  extremely  volatile  liquid  with  a  very  disagree¬ 
able  odor  unless  obtained  pure,  when  it  is  much  more  expensive. 
The  fumes  are  heavier  than  air,  so  that  it  is  always  best  to  expose 
the  liquid  in  the  upper  part  of  a  building,  or  other  receptacle  con¬ 
taining  objects  to  be  treated.  The  fumes  are  explosive  also  when 
mixed  with  air,  so  that  great  care  must  be  taken  not  to  bring  fire 
near  them. 

For  the  purpose  of  fumigating  a  building  or  other  inclosed 
space  containing  growing  plants,  not  over  one  pint  of  the  liquid  to 
1,000  cubic  feet  of  space  should  be  used.  For  the  destruction  of 
insects  in  seeds,  carpets  or  clothing  it  may  be  used  much  stronger. 

To  destroy  ant  hills,  thrust  a  sharp  stick  down  into  the  hill 
to  a  depth  of  eight  or  ten  inches  and  then  remove  it  and  pour  in 
two  or  three  ounces  of  the  carbon  bisulfide;  fill  the  hole  with  earth 
by  stamping  on  it,  and  then  throw  over  the  hill  a  wet  blanket  to 


40 


THE  COLORADO  EXPERIMENT  STATION 


hold  down  the  fumes.  Allow  the  blanket  to  remain  for  a  half  hour 
at  least,  and  the  ants  will  be  dead.  If  the  hill  is  a  very  large  one 
it  would  be  well  to  make  two  or  three  holes  for  the  carbon  bisul¬ 
fide. 

To  kill  prairie  dogs,  pour  three  or  four  ounces  of  the  liquid 
on  a  ball  of  cotton  and  roll  the  latter  down  the  prairie  dog  hole  and 
quickly  fill  the  mouth  of  the  hole  with  dirt.  Dry  horse  droppings 
or  pieces  of  gunny  sacking  may  be  used  in  place  of  the  cotton. 

For  the  destruction  of  the  woolly-louse  of  the  apple,  thrust  a 
crow-bar  or  other  sharp  instrument  into  the  ground  to  the  depth  of 
one  foot  or  a  little  more,  and  at  a  distance  of  two  feet  from  the 
crown  of  the  tree  and  upon  three  sides  of  the  tree.  In  each  of 
these  holes  pour  one  ounce  of  the  carbon  bisulfide  and  close  the 
holes  quickly  with  damp  earth.  This  is  a  cheap  and  effectual 
remedy  and,  if  care  is  taken  to  have  the  holes  made  two  feet  from 
the  tree  and  to  have  only  about  an  ounce  of  the  liquid  put  in  a 
hole,  there  will  be  little  or  no  danger  of  killing  the  trees. 

This  substance  is  expensive  when  purchased  in  small  quanti¬ 
ties  at  a  drug  store.  It  may  be  obtained  quite  cheaply  if  pur¬ 
chased  in  50-pound  lots,  from  Mr.  Edward  R.  Taylor,  Cleveland, 
Ohio.  Write  for  prices. 

27.  HYDROCYANIC  ACID  GAS. 

This  gas  has  come  into  very  general  use,  particularly  in  the 
orange  growing  sections  of  the  country,  for  the  destruction  of  scale 
insects.  It  may  also  be  used  for  the  destruction  of  insects  in  mills 
and  in  dwellings  and  in  closed  receptacles  generally.  Some  of  the 
best  nursery  men  have  adopted  the  excellent  plan  of  fumigating  all 
their  nursery  stock  with  hydrocyanic  acid  gas  before  shipping  to 
their  customers.  This  should  always  be  done. 

The  chemicals  of  which  this  gas  is  made  are  cheap  and  are 
used  in  the  following  proportions: 

Potassium  cyanide  (of  98  per  cent,  purity)  —  1  ounce. 


Commercial  sulfuric  acid . 1  ounce. 

Water . 3  ounces. 


The  above  quantities  are  sufficient  for  a  space  of  100  cubic  feet 
for  the  fumigation  of  dormant  trees  and  plants  (nursey  stock).  It 
may  be  used  in  the  same  strength,  or  even  stronger,  for  the  fumi¬ 
gation  of  mills,  houses,  clothing  and  the  like. 

The  tent,  building  or  receptacle  in  which  the  fumigation  is  to 
take  place,  should  be  as  tight  as  possible.  The  less  wind  there  is 
the  better,  if  the  fumigating  room  is  not  very  tight. 

The  gas  should  be  generated  in  an  earthen  jar,  or  wooden 
bucket  or  tub.  The  chemicals  must  be  added  hi  the  following 
order:  First  put  in  the  water;  then  add  the  acid;  and,  after  the 


INSECTS  AND  INSECTICIDES 


41 


water  and  acid  have  mixed,  add  the  potassium  cyanide.  A  good 
way  to  add  the  poison  is  to  have  it  tied  in  a  paper  sack  and  placed 
upon  a  piece  of  board  over  the  dish  containing  the  acid  and  water, 
with  a  string  attached  to  the  sack  and  passing  to  the  outside. 
Then,  when  everything  has  been  made  tight,  a  puli  on  the  string 
will  precipitate  the  sack  of  cyanide  in  the  acid  and  a  rapid  escape 
of  the  poisonous  fumes  (HCN)  will  immediately  take  place,  caus¬ 
ing  violent  bubbling  of  the  liquid.  Filling  ones  lungs  with  these 
fumes  would  cause  almost  instant  death,  so  great  care  must  be  taken 
not  to  breathe  them.  Fumigating  rooms  must  be  arranged  so  that 
doors  or  windows  of  some  sort  can  be  raised  from  the  outside 
quickly.  Then  a  thorough  airing  must  take  place  before  anyone 
enters. 

It  would  require  considerable  space  to  give  full  directions  for 
the  fumigation  of  orchard  trees,  and,  as  there  is  little  likelihood  that 
such  fumigation  will  be  called  for  in  Colorado  for  some  time  to 
come,  I  shall  not  take  space  to  describe  the  process  here.  Those 
specially  interested  can  obtain  bulletins  giving  full  directions  from 
the  Deparnment  of  Agriculture,  Division  of  Entomology,  Washing¬ 
ton,  D.  C.  Full  directions  can  also  be  obtained  in  a  book  entitled 
“Fumigation  Methods,”  by  W.  G.  Johnson,  and  published  by 
Orange  Judd  Co.,  New  York. 

SUBSTANCES  THAT  REPEL. 

There  are  a  number  of  substances  that  are  more  or  less  useful 
for  the  purpose  of  driving  insects  away  from  places  where  they 
would  cio  harm  if  unmolested.  I  give  below  a  few  of  the  most 
important. 

28.  NAPTHALINE,  GUM-CAMPHOR,  AND  MOTH  BALLS. 

Napthaline  crystals  are  much  used  in  insect  boxes  and  in  boxes 
or  trunks  where  furs,  feathers  or  woolen  gooods  are  kept,  for  the 
purpose  of  keeping  out  insects  that  feed  on  these  animal  products. 
It  is  probably  the  best  single  chemical  that  can  be  used  for  this 
purpose.  Gum-camphor  is  also  much  used  for  the  same  purpose 
and  moth-balls  are  a  combination  of  these  two  volatile  substances. 
These  materials  cannot  be  used  to  kill  insects,  but  onlv  to  repel 
them. 

29.  TOBACCO. 

Tobacco,  in  the  form  of  dust,  or  otherwise,  is  often  used  for 
the  same  purpose  as  the  preceding,  but  to  be  effectual  must  be  used 
quite  freely. 

30.  ASHES. 

Ashes,  particularly  from  wood,  are  frequently  used  to  dust 


42 


THE  COLORADO  EXPERIMENT  STATION 


upon  plants  after  a  rain  or  while  the  dew  is  on  and  often  result  in 
the  insects  disappearing.  Particularly  is  this  true  in  case  of  flea- 
beetles  and  the  cucumber  beetle  when  feeding  upon  leaves.  Ashes 
do  not  kill  the  insects,  but  they  make  the  food  distateful,  so  the 
insects  are  driven  to  other  plants. 

31.  LIME,  PLASTER,  AND  ROAD  DUST. 

These  substances  are  also  used  like  ashes  as  repellents,  but  are 
of  little  or  no  use  for  the  destruction  of  insects,  except,  possibly, 
the  pear  and  cherry  tree  slugs. 

INSECT  TRAPS. 

There  are  many  methods  of  trapping  and  destroying  insects* 
One  of  the  most  common  is  the  use  of  bright  lights  exposed  at 
night. 

32.  LIGHTS. 

The  usual  plan  is  to  place  a  light  over  a  dish  of  some  sort  that 
contains  water  with  coal  oil  on  top  of  it.  Many  night-flying  insects 
are  attracted  by  lights  and  may  be  destroyed  by  devices  of  this  kind, 
but  there  are  also  many  insects  that  fly  at  night  that  are  not  at¬ 
tracted  by  lights.  Such  an  insect  is  the  codling  moth,  though 
light  traps  are  often  recommended  for  its  destruction.  Among 
those  insects  that  are  readily  attracted  by  lights  might  be  men¬ 
tioned  the  adults  of  the  army  worm,  of  the  various  cut-worms,  the 
garden  web-worms,  the  corn  or  boll-worm,  and  the  beet-worms. 

It  is  not  infrequently  the  case  that  more  of  the  beneficial  in¬ 
sects  are  destroyed  than  of  destructive  species,  and  it  is  quite  doubt¬ 
ful  if  lights  are  often  of  any  great  importance  as  a  means  of  lessen¬ 
ing  the  injury  to  crops  by  the  destruction  of  insects. 

33.  SWEETENED  WATER,  CIDER,  VINEGAR,  ETC. 

Some  insects  are  attracted  in  considerable  numbers  to  such 
substances  as  the  above,  but  it  is  very  seldom  that  the  benefit  derived 
from  them  will  pay  for  the  trouble  and  expense  of  using  them. 
Mr.  David  Brothers,  of  Edgewater,  Colo.,  reported  excellent  success 
capturing  moths  of  the  fruit-tree  leaf-roller  with  weakened  vin¬ 
egar  in  pans  in  the  orchard,  and  the  codling  moth  is  attracted  to 
some  extent  to  a  mixture  of  molasses  and  vinegar  placed  in  apple 
trees.  The  advantage  of  such  baits  for  the  capture  of  insects  is 
usually  greatly  overstimated  by  those  who  use  them. 

34.  BANDAGES. 

Heavy  cloth  or  paper  bands  placed  about  the  trunks  of  apple 
trees  are  quite  useful  for  the  capture  of  the  larvae  of  the  codling 


INSECTS  AND  INSECTICIDES 


43 


moth  that  are  leaving  the  apples  and  going  in  search  of  a  suitable 
place  to  spin  their  cocoons.  Burlap  bands  are  cheap  and  seem  to 
be  as  good  as  any.  'The  writer  took  1,481  codling  moth  larvae 
under  a  single  burlap  band  one  season.  Old  gunny  sacks  cut  into 
strips  serve  as  well  as  anything.  The  band  should  not  be  less  than 

four  inches  wide  and  should  be  composed  of  three  thicknesses  of 
the  cloth. 

The  bands  should  be  wrapped  loosely  about  the  trunks,  the 
ends  overlapped  and  held  in  place  by  a  single  carpet  tack  pushed 
in  with  the  thumb. 

If  used  against  the  codling  moth  they  should  be  removed 
once  in  a  week  or  ten  days  for  the  purpose  of  killing  all  the  worms 
and  then  replaced. 

The  bands  should  be  placed  on  the  trees  about  the  10th  of 
June  in  the  warmer  parts  of  the  State,  and  about  the  20th  of  June 
in  the  northern  parts. 

Bands  of  paper  or  wire  screen  are  sometimes  wrapped  about 
the  entire  trunk  to  prevent  the  entrance  of  borers,  as  shown  in 
Plate  4  Figs.  2  and  3. 

35.  HOPPER-DOZERS  OR  HOPPER-PANS. 

For  the  purpose  of  catching  jumping  insects,  especially  grass¬ 
hoppers,  the  hopper-dozer  or  hopper-pan  is  most  useful.  The  re  are 
different  methods  of  constructing  these  pans.  A  form  used  by  Dr. 
Riley  and  illustrated  by  him  many  years  ago  is  shown  at  P hg.  2. 
The  pan  in  the  illustration  is  entirely  of  sheet-iron,  and  is  drawn 
across  the  field  by  two  men  or  two  horses.  In  the  bottom  of  the 
pan  is  placed  a  small  amount  of  water  with  kerosene  on  it.  All 
grasshoppers  that  come  in  contact  with  the  oil  die.  The  back  of 
the  pan  may  be  extended  by  means  of  stakes  at  the  corners  and  a 
strip  of  cloth  hung  between  them.  Such  an  extension  catches 
many  grasshoppers  that  would  otherwise  escape.  A  modification  of 
this  pan  is  shown  in  bulletin  No.  112,  of  this  station  by  Mr 
P.  K.  Blinn. 

36.  STICKY  SUBSTANCES. 

Bandages  of  sticky  substances,  such  as  printer’s  ink,  uDen- 
droline,”  “Raupenleim,”  “Tree  Tangle-PAoot”  or  even  cotton 
batting,  are  sometimes  used  to  prevent  insects  from  climbing  trees. 
Where  oily  substances  are  used  it  is  safer  to  put  them  on  a  bandage 
of  stout  paper,  which  is  then  wrapped  about  the  trunk  of  the  tree. 

THE  APPLICATION  OF  INSECTICIDES. 

I  think  it  best  not  to  attempt  to  show  types  of  apparatus  for 


44 


THE  COLORADO  EXPERIMENT  STATION 


the  application  of  insecticides  in  this  bulletin.  There  are  so  many 
manufacturers  of  spraying  machinery  now  that  it  would  be  impos¬ 
sible  to  show  pumps  and  other  appliances  made  by  more  than  a  few 
of  them.  At  the  close  of  this  article  is  a  list  of  some  of  the  more 
prominent  dealers  in  spraying  machinery.  One  who  contemplates 
purchasing  spraying  apparatus  should  write  to  a  few  of  these  firms 
for  catalogues,  and  then  select  what  seems  to  be  the  pump  or  other 
machine  that  is  best  suited  to  his  needs.  Advertisements  of  other 
dealers  in  spraying  machinery  may  be  found  in  papers  and  maga¬ 
zines  devoted  to  agricultural  and  horticultural  pursuits. 

APPLICATION  OF  DRY  INSECTICIDES. 

The  upper  surface  of  the  leaves  of  all  low  plants  can  be  easily 
treated  with  a  dry  insecticide  by  dusting  it  through  a  cheesecloth, 
or  other  thin  muslin  bag  held  in  the  hand.  There  are  also  various 
dust  sprayers  of  large  and  small  sizes  upon  the  market. 

By  whatever  means  the  dust  is  distributed  it  is  best  applied 
in  the  evening  or  early  morning  when  foliage  is  slightly  moistened 
with  dew,  or  after  a  shower. 

APPLICATION  OF  WET  INSECTICIDES. 

THE  PUMPS. 

Pumps  with  metal  valves  should  be  obtained  for  the  applica¬ 
tion  of  insecticides  or  fungicides  in  liquid  form,  as  the  materials 
used  harden  or  decompose  leather  valves  so  that  they  last  but  a 
short  time.  If  the  pump  is  to  be  used  with  a  tank  or  barrel  it  is 
also  important  to  have  some  kind  of  attachment  that  will  keep  the 
liquid  agitated  so  the  materials  in  suspension  will  not  settle.  A 
common  error  is  to  purchase  a  pump  of  too  small  capacity,  because 
it  is  cheaper.  A  smaller,  cheaper  pump  usually  means  less  accom¬ 
plished  in  a  day  with  same  help  and  a  poorer  job,  with  a  greater 
expenditure  of  labor.  And  then,  it  is  often  important  to  complete 
the  spraying  in  as  short  a  time  as  possible  after  it  is  begun.  To  do 
this,  a  pump  of  large  capacity  with  two  or  more  leads  of  hose  is 
necessary.  The  hose  to  which  the  nozzles  are  attached  should  be 
as  light  as  possible  and  still  have  the  requisite  strength — a  hose  of 
good  quality  with  heavy  wall,  but  small  caliber.  Bucket  pumps 
are  sold  by  different  dealers  at  prices  ranging  between  about  $2.00 
and  $8.00  in  price.  They  are  suitable  for  use  among  garden  vege¬ 
tables,  shrubbery  and  all  low  plants,  but  should  not  be  purchased 
for  orchard  work  if  one  has  more  than  a  very  few  trees  to  treat. 

If  one  has  light  spraying  to  do  and  is  without  help,  the  com¬ 
pressed  air  sprayers  are  very  convenient.  Large  compressed  air 
sprayers  that  derive  their  power  from  gearing  attached  to  the 


INSECTS  AND  INSECTICIDES 


45 


wagon  wheel  are  specially  adapted  to  the  treatment  of  low  plants, 
bnt  I  very  much  doubt  if  any  spraying  machines  of  this  class  upon 
the  market  are  well  adapted  to  the  spraying  of  large  orchard  trees 
where  the  wagon  must  stand  still  a  large  proportion  of  the  time 
while  the  spraying  is  going  on. 

Where  large  orchards  are  to  be  sprayed  it  is  a  matter  of  neces¬ 
sity  and  economy  to  use  tanks  that  will  hold  200  and  300  gallons, 
and  pumps  of  large  capacity.  In  such  orchards  gasoline  powei 
sprayers  are  most  useful. 

HOW  TO  SPRAY. 

The  first  requisite  for  a  good  job  of  spraying  is  a  pump  that 
will  give  plenty  of  pressure  in  the  hose.  Then,  if  one  has  a  good 
spraying  nozzle  and  a  liquid  that  is  free  from  solid  particles  of  a 
size  to  clog  the  sprayer,  there  will  be  no  difficulty  in  gettingagood 
spray.  Barrels  and  tanks  should  always  be  filled  through  a  strainer 
to  avoid  loss  of  time  and  annoyance  through  the  cloo-oinp-  of 
nozzles.  '  8 

A  very  fine  spray  is  most  economical  of  material  and,  for 
an  even  and  thorough  distribution,  is  best,  and  is  specially  useful 
for  the  destruction  of  caterpillars,  slugs  and  other  insects  that 
devour  the  foliage  of  plants.  In  case  of  the  first  spraying  for  the 
codling  moth,  however,  I  am  still  constrained  to  recommend  as  I 
have  done  for  years,  that  the  spray  be  a  medium  coarse  one.  By 
this  I  do  not  mean  that  the  spray  should  be  composed  largely  of 
large  drops  produced  by  the  breaking  up  of  a  solid  stream  Thrown 
forcibly  into  the  air,  and  it  should  not  be  a  fine  mist  or  fog.  A 
rather  coarse  Vermorel,  or  a  good  Bordeaux  nozzle  with  a  pressure 
of  100  or  125  pounds,  will  furnish  such  a  spray  as  I  refer  to.  When 
spraying  is  being  done  to  destroy  leaf-eating  insects,  care  should 
be  taken  not  to  spray  too  long  in  one  place,  as  this  will  result  in 
the  little  drops  that  collect  upon  the  leaves  uniting  and  running 
off,  carrying  the  poison  with  them.  Here  again  this  rule  does  not 
apply  to  the  first  treatment  for  the  codling  moth.  In  that  applica¬ 
tion  there  should  be  but  one  end  in  view,  and  that  to  fill  every 
blossom  or  calyx  cup  with  the  spray. 

NOZZLES  TO  USE. 

There  are  two  types  of  nozzles  that  are  used  almost  exclu¬ 
sively  for  the  distribution  of  liquids.  Perhaps  the  most  popular 
among  these  are  the  Bordeaux  and  Seneca  nozzles  which 
throw  a  flat  spray  or  a  solid  stream,  and  the  Vermorel  noz¬ 
zles  which  throw  a  cone  shaped  spray  which  may  be  graded  from 
medium  coarse  to  extremely  fine  depending  upon  the  pressure  and 
the  tip  that  is  used  upon  the  nozzle.  It  is  a  big  advantage  in  noz- 


46 


THE  COEORADO  EXPERIMENT  STATION 


zles  of  this  class  to  have  them  joined  to  the  connecting  rod  so  they 
may  be  turned  at  any  angle  to  the  rod  that  is  desired. 

Any  of  these  nozzles  may  be  used  singly  or  in  batteries  of  two 
to  four. 


SOME  LEADING  MANUFACTURERS  OF  SPRAYING  MACHINERY. 

The  Gould  Manufacturing  Co.,  Seneca  Falls,  N.  Y. 

The  Deming  Co.,  Salem,  Ohio. 

The  C.  E.  Brown  Co.,  47  Jay  Street,  Rochester,  N.  Y. 

The  Friend  Manufacturing  Co.,  Gasport,  N.  Y. 

The  Hook-Hardie  Co.,  Hudson,  Mich. 

Dayton  Supply  Co.,  Dayton,  Ohio. 

F.  E.  Meyers  &  Bro.,  Ashland,  Ohio. 

Bean  Spray  Pump  Co.,  San  Jose,  California. 

Spramotor  Co.,  107-109  Erie  Street,  Buffalo,  N.  A. 

Wallace  Machinery  Co.,  Champaign,  Ill. 

Morrill  &  Morley,  Benton  Harbor,  Mich. 

William  Stahl,  Quincy,  111. 

Fairbanks,  Morse  &  Co.,  Denver,  Colo. 

Webber  Fngine  Co., 

Dean  Power  Pump  Co.,  Holyoke,  Mass. 

Field  Force-Pump  Co.,  Elmira,  N.  Y. 

International  Harvester  Co.,  Denver,  Colo. 


A<: 


mmmm 


Spray  tank  and  hand  pump  used  with  excellent  results  by  Senator  J.  W.  Crowley, 
in  his  large  orchards  at  Rocky  Ford,  Colorado. 


May,  1906 


UN1VEKSITV  of  ILLINOIS 


Bulletin  115 


The  Agricultural  Experiment  Station 

OF  THE 

Colorado  Agricultural  College 


Fertilizer  Experiments  With  Sugar  Beets 


By 


A.  H.  DANIELSON 


< 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
FORT  COLLINS,  COLORADO 
1906 


THE  AGRICULTURAL  EXPERIMENT  STATION 

FORT  COLLINS,  COLORADO 


THE  STATE  BOARD  OF  AGRICULTURE 

Hon.  P.  F.  SHARP,  President ,  -------  Denver, 

Hon.  HARLAN  THOMAS,  -  ------ 

Hon.  JAMES  L.  CHATFIELD,  ------ 

Hon.  B.  U.  DYE,  -  -  ------- 

Hon.  B.  F.  ROCKAFELLOW,  ------ 

Hon.  EUGENE  H.  GRUBB  -  -  -  -  -  - 

Hon  A.  A.  EDWARDS.  ------- 

Hon.  R.  W.  CORWIN,  ------- 

Governor  JESSE  F.  McDONALD,  [  ~  . 

President  BARTON  O.  AYLESWORTK,  \eX~°  lcl0' 

A.  M.  HAWLEY,  Secretary  EDGAR  AVERY,  Treasurer 

EXECUTIVE  COMMITTEE  IN  CHARGE 

P.  F.  SHARP,  Chairman 


terms 

expires 

Denver, 

-  1907 

Denver, 

-  1907 

Gypsum, 

-  1909 

Rockyford, 

1909 

Canon  City 

-  1911 

Carbon  dale, 

-  1911 

Fort  Collins, 

-  1913 

Pueblo 

-  1913 

B.  F.  ROCKAFELLOW. 


A.  A.  EDWARDS. 


STATION  STAFF 

L.  G.  CARPENTER,  M.  S.,  Director ,  -----  Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S.,  -  -----  -  Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D.,  ____  _  ____  Chemist 

W.  PADDOCK,  M.  S.,  -  -----  -  Hortulculturist 

W.  L.  CARLYLE,  M.  S.,  -  -  -  -  -  -  -  -  -  -  Agriculturist 

G.  H.  GLOVER,  B.M.  S.,  D.  V.  M.,  --------  Veterinarian 

W.  H.  OLIN,  M.  S.,  -  --  --  --  --  --  Agronomist 

R.  E.  TRIMBLE,  B.  S.,  -----  Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S.,  -  --  --  --  -  -  Assistant  Chemist 
EARL  DOUGLASS,  M.  S ,  -  -  -  -  -  -  -  -  Assistant  Chemist 

S.  ARTHUR  JOHNSON,  M.  S.,  -  -  -  -  -  -  Assistant  Entomologist 

B.  O.  LONGYEAR,  B.  S.,  -  -  -  -  -  -  Assistant  Horticulturist 

J.  A.  McLEAN,  A.  B.,  B.  S.  A  ,  -  -  -  -  -  -  -  Animal  Husbandman 

E.  B.  HOUSE,  M.  S.,  ------  Assistant  Irrigation  Engineer 

F.  KNORR,  -  --  --  --  --  -  Assistant  Agriculturist 

P.  K.  BLINN,  B.  S.,  -  -  -  -  Field  Agent  Arkansas  Valley,  Rockyford 

E.  R.  BENNETT,  B.  S.,  -  -  -  -  -  Potato  Investigations 

Western  Slope  Fruit  Investigations,  Grand  Junction: 

O.  B.  WHIPPLE,  B.  S.,  -  -  --  --  _  _  Field  Horticulturist 

E  P.  TAYLOR,  B.  S.,  -  -  -  -  -  -  -  -  Field  Entomologist 


OFFICERS 


President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 
L.  G.  CARPENTER,  M.  S.,  -  -  -  -  -  -  -  -  -  - 

A.  M.  HAWLEY,  ------------ 

MARGARET  MURRAY,  -  -  -  ------ 


Director 

Secretary 

Clerk 


Fertilizer  Experiments  With  Sugar  Beets 

BY  A.  H.  DANIELSON  * 


These  experiments  extended  over  three  years,  1903,  ’04  and  ’05, 
and  were  to  test  the  effect  of  fertilizers  on  the  yield  and  quality  of 
sugar  beets  and  determine  the  effect  from  the  different  fertilizers  used, 
under  field  conditions,  and  incidentally  a  number  of  other  questions. 

The  tests  of  1903-04  were  on  plats  of  one-tenth  of  an  acre  on 
the  College  farm,  the  plats  used  in  the  two  years  not 'being  the  same. 
The  test  of  1*903  was  of  the  nature  of  a  preliminary  test.  A  coopera¬ 
tive  test  with  the  Department  of  Agriculture  formed  one  of  the  series 
of  tests  by  the  Buieau  of  Chemistry  on  the  ^Influence  of' Environ¬ 
ment.  upon  the  Composition  of  the  Sugar  Beet.”  In  1905  corres¬ 
ponding  tests  were  made  with  plats  of  six-tenths  of  an  acre  each  in 
a  field  being  raised  under  field  conditions. 

With  the  change  in  conditions  brought  by  the  cultivation  of  sugar 
beets  the  necessity  which  is  being  felt  for  artificial  fertilizers,  the  ex¬ 
haustion  of  the  supply  of  sheep  manure  which  has  been  the  common 
source  for  a  number  of  years,  and  the  consequent  realization  of  the 
future,  if  not  the  present,  importance  of  fertilization,  led  to  the  tests 
here  given. 

Further  and  additional  tests  are  desirable  but  it  is  believed  the 
results  are  of  value  as  they  are. 

Fertilizer  Experiments  in  1903. — The  experiments  conducted  this 
season  were  in  the  nature  of  a  preliminary  test.  The  most  complete 
series  of  plats  was  carried  out  on  Field  F,  although  there  it  is  defective 
for  an  ‘ideal  series  in  that  potash  was  left  out  except  in  the  complete 
fertilizer  as  the  experiment  was  planned  too  late  to  secure  potash 
fertilizers. 

The  main  object  of  this  trial  on  Field  F  was  to  determine  the 
effect  of  an  excessive  quantity  of  stable  manure  on  beets,  that  of  a 
fairly  large  application,  and  a  small  quantity  with  nitrate  of  soda,  as 
compared  with  nitrate  and  phosphates  alone  and  complete  fertilizers. 
The  result  of  the  application  of  these  materials  in  1903  on  this  field 
is  of  more  than  ordinary  interest  because  the  after  or  residual  effects 
of  those  applied  in  1903  were  tested  for  the  two  succeeding  years. 
This  data  is  given  later. 

*  Assist  ant  Agriculturist  1900-Jan.  1,  1903. 


4 


BULLETIN  115. 


Crop  History  of  Field  F  Used  1903. — The  soil  during  1901  and 

1902  was  very  lumpy  and  especially  in  1901  in  poor  physical  condi¬ 
tion  because  being  plowed  when  very  wet  in  1900.  The  crops  begin¬ 
ning  with  1900  have  been  as  follows: 

1900 —  Plats  of  grain,  sugar  beets  and  corn. 

1901 —  Sugar  beets,  10  tons  per  acre. 

1902 —  Grains  1413  pounds  per  acre,  as  follows,  wheat  756  pounds, 
oats  271,  barley  256,  rye  62  and  emmer  68  pounds. 

1903 —  Sugar  beets,  23.5  tons  per  acre,  with  manure  and  fertili¬ 
zer. 

1904 —  Sugar  beets  17.6  tons  per  acre. 

1905 —  Sugar  beets  16.0  tons  per  acre.  .  . 

The  chemical  analysis  of  the  soil  and  subsoil  from  this  field  in 

1903  and  1904,  is  given  in  Bulletins  95  and  96,  U.  S.  Bureau  Chemistry. 
The  field  was  plowed  the  preceding  fall  (1902),  disc  harrowed  the 
next  spring  on  April  17.  The  fertilizer  was  applied  on  April  18,  on  all 
plats  except  1,  2  and  3,  by  distribution  with  a  drill  on  top  of  the  soil 
and  thorough  harrowing  with  a  drag  harrow  the  long  way  of  the  plats. 
The  cow  manure  on  Plats  1,  2  and  3  was  applied  April  11-17,  plowed 
under,  harrowed  on  the  18th;  the  nitrate  applied  to  Plat  3,  when  the 
manure  had  been  plowed  under,  and  harrowed  into  the  soil  together 
with  the  balance  of  the  fertilizers  on  April  18.  The  seed  was  planted  in 
rows  twenty  inches  apart  at  the  rate  of  fifteen  pounds  per  acre  on 
April  21;  Plats  9  and  10  on  April  27.  The  seed  used  was  the  variety 
known  as  Kleinwanzlebener  grown  in  the  State  of  Washington. 

The  cow  manure  used  was  without  straw  or  litter,  almost  fresh, 
being  only  three  and  a  half  months  old.  It  was  the  intention  to  use 
well  rotted  sheep  manure,  but  none  was  available  at  the  time.  The 
bone  meal  was  odorless,  probably  from  steamed  bones,  or  from 
“prairie  bones. ”  The  two  complete  fertilizers  consisting  of  nitrogen 
estimated  as  ammonia,  3.5 — 4.5%;  available  phosphoric  acid  8-10%; 
potash  6-8%,  were  made  up  especially  for  this  experiment  by  a  fertil¬ 
izer  firm. 

The  beets  were  hoed  and  thinned  from  May  30  to  June  4.  On 
June  6-10  a  heavy  rain  set  in  amounting  to  two  inches  in  depth. 
Only  two  irrigations  were  given,  on  July  3  and  23.  On  August  10, 
Plat  10,  with  the  excessive  quantity  of  manure  had  the  rankest  growth 
of  leaves.  The  three  manured  plats  were  more  thrifty  than  those  fer¬ 
tilized.  Plat  5,  bone  meal  and  nitrate,  show  better  growth  than  No. 
4,  with  nitrate  alone.  Plat  8,  with  Basic  slag  appears  better  than 
the  bone  meal  plat.  Plat  10,  complete  fertilizer,  looks  better  than 
the  adjacent  plat  with  less  nitrogen  from  nitrates. 

On  November  7th  the  samples  for  analyses  were  taken.  The  har¬ 
vesting  and  weighing  began  on  November  14  with  Plat  No.  1,  and  was 
not  finished  until  November  25.  Plats  1  to  6,  inclusive,  were  harvested 
November  14-16,  although  Plat  6  was  not  weighed  until  November 
24.  Plats  7-10,  inclusive,  were  harvested  and  weighed  November 
23-25.  Where  the  piles  of  beets  could  not  be  hauled  and  weighed  at 
once  they  were  covered  with  a  layer  of  beet  leaves  and  soil  in  order  to 


FERTILIZER  EXPERIMENTS  WITH  SUGAR  BEETS.  5 

prevent  freezing,  and  this  also  checked  loss  in  weight  from  evapora¬ 
tion  or  drying  out. 

In  applying  the  fertilizer  and  manure  a  strip  two  feet  wide  was 
left  between  each  two  plats  to  which  nothing  was  applied.  The  rows 
of  beets  which  grew  on  these  strips  were  measured  and  harvested 
separately,*  weighed  and  counted.  It  will  be  seen  that  the  average 
weight  per  beet  in  these  rows  between  the  plats  is  0.7  of  a  pound  less 
than  the  average  weight  given  in  Table  1 1  of  the  samples  taken  for  analy¬ 
sis.  While  the  estimated  average  tonnage  per  acre  of  these  rejected 
rows  is  only  1.5  tons  less  than  the  actual  average  yields  of  all  the  plats. 
While  no  fertilizer  was  applied  to  the  rows  between  the  plats,  practi¬ 
cally  a  great  deal  would  be  worked  within  reach  of  the  roots  from  that 
applied  on  both  sides.  From  this  data  it  is  fair  to  assume,  that  in 
spite  of  great  care  in  selecting  the  samples  the  average  weight  of  the 
beets  chosen  for  analysis  to  represent  the  sugar  content  and  purity 
of  each  plat  is  about  one-third  larger  than  the  average  weight  per  beet 
of  all  the  beets  harvested.  Nearly  the  same  proportion  is  found  be¬ 
tween  the  twelve  beets  analyzed  from  Plat  6  and  366  beets  dug  for 
the  same  plat  to  note  changes  in  maturing,  reported  in  Table  17. 
However,  the  samples  for  analysis  were  selected  in  exactly  the  same 
way,  so  that  the  results  were  strictly  comparable  between  themselves. 
This  particular  part  of  the  data  obtained  shows  that  the  120  beets 
carefully  selected  to  represent  the  whole  field,  were  actually  one 
third  larger  than  1,902  beets  actually  harvested. 


Table  5. 

FERTILIZERS  ON  FIELD  F,  1903 — ONE-TENTH  ACRE  PLATS 


Plat 

No. 

KIND  OF  FERTILIZER 
(Per  Acre) 

/ 

Cost  of 
Fertil¬ 
izer 
per 
acre 

Yield 

of 

Clean 

Beets 

per 

acre 

Sugar 

in 

Beets 

Pur¬ 

ity 

Co¬ 

effi¬ 

cient 

Amt. 
Rec’v’d 
pr.  acre 
for 
Beets 

Amt. 

Rec’d 

less 

30St  Of 

Fertil¬ 

izer 

1 

Cow  Manure . 60  tons 

$45.00 

Tons 

24.11 

Per  Ct. 
13.1 

81.0 

$120.55 

$  75.55 

2 

Cow  Manure . 30  tons 

22.50 

25.10 

14.3 

82.8 

125. 5( 

103.00 

3 

Cow  Manure . 15  tons 

Nitrate  of  Soda . 150  pounds 

15.75 

25.25 

14.4 

84.2 

126.25 

110.50 

4 

Nitrate  of  Soda . i 50  pounds 

4.50 

25.67 

13.3 

83.3 

128.35 

123.85 

5 

Nitrate  of  Soda . 150  pounds 

Raw  Bone  Meal . 200  pounds 

7.10 

25.61 

14.9 

83.8 

128.05 

120.95 

6 

No  Fertilizer 

21.46 

15.1 

85.0 

107. 3C 

107.30 

7 

Raw  Bone  Meal . 2C0  pounds 

2.60 

21.72 

15.1 

87.3 

108. 6( 

106.00 

8 

Thomas  Phosphate . 400  pounds 

(or  Basic  Slag) 

6.00 

22.60 

15.1 

84.4 

113. 0< 

107.00 

9 

Complete  Fertilizer . 

Nitrate  of  Soda . TO  pounds 

Dried  Blood  . 75  pounds 

Acid  Bone  Meal . 250  pounds 

Sulphate  of  Potasli . 50  pounds 

Carbonate  of  Potash . 75  pounds 

(from  Tobacco  Ashes) 

10.00 

20.63 

16.1 

87.9 

103.15 

93.15 

10 

Complete  Fertilizer . 

Nitrate  of  Soda .  .100  pounds 

Dried  Blood . '25  pounds 

Acid  Bone  Meal . 250  pounds 

Sulphate  of  Potash . 75  pounds 

Carbonate  of  Potash . 50  pounds 

(from  Tobacco  Ashes) 

10.00 

22.35 

14.6 

84.4 

111.75 

101.75 

Average . 

23.45 

14.6  !  X4.4 

117.25 

. 

6 


BULLETIN  115. 


Some  interesting  results  are  shown  from  the  expertments  on  Field 
F,  in  1903,  which  can  be  a  little  better  understood  on  account  of  the 
data  obtained  from  the  same  plats  for  the  next  two  years. 

The  difference  in  effect  of  the  fertilizers  and  manures  is  greater 
than  could  reasonably  be  expected,  when  it  is  seen  that  this  soil  with¬ 
out  manure  or  fertilizer  was  able  to  produce  about  21.5  tons  per  acre. 


Table  6. 

DATA  IN  REGARD  TO  NEGLECTED  ROWS  BETWEEN  FERTILIZED  PLATS — 
FIELD  F,  1903,  FROM  A  MEAN  OF  154  BEETS  PER  ROW 


Row  Estimated 

Between  Yield 

Plats  Per  Acre 


Number  Tons 


0-1  24.14 

1- 2  25.85 

2- 3  20.50 

3- 4  27.01 

4- 5  22.58 

5- 6  •  19.16 

6- 7  .  19.24 

7- 8  20.52 

8- 9  20.06 

9- 10  20.06 

Averages . 21.91 


Average 

Weight 

Per  Beets 

Average 

Space 

Between  Beets 
in  Row 

Pounds 

Inches 

1.67- 

11.3 

1.51 

9.6 

1.16 

9.0 

1.59 

9.6 

1.32  ‘ 

9.6 

1.20 

10.3 

1.30 

11.0 

1.13 

8.9 

1.37 

10.4 

1.39 

10.6 

1.36 

10.0 

The  effect  of  the  excessive  quantity  of  manure,. Plat  1,  was  not 
as  injurious  to  the  quality  of  the  beet  as  might  be  expected,  only  about 
two  per  cent  less  sugar  and  four  points  less  in  purity  than  the  plats 
yielding  less.  The  yield  was  also  about  a  ton  less  than  the  other 
manured  plats,  while  the  beets  although  larger  were  of  poorer  shape. 

The  phosphoric  acid  used  alone  from  bone  meal  and  Basic  slag, 
Plats  7  and  8,  had  very  little  if  any  effect  on  increasing  the  yield, 
although  the  Basic  slag  produced  a  ton  more  beets  than  the  bone  meal, 
which  alone  had  practically  no  effect  on  the  yield  of  beets.  Used 
with  nitrate  of  soda  on  Plat  5,  we  may  presume  it  would  be  equally 
ineffective.  The  highest  yields  of  any  of  the  fertilizers  was  from  the 
Plats  4  and  5  where  nitrate  of  soda  was  used  at  the  rate  of  150  pounds 
per  acre.  This  is  a  little  more  than  the  result  from  the  plat  of  thirty 
tons  manure  or  4.1  tons  more  than  the  unfertilized  plat.  The 
nitrate  of  soda  and  fifteen  tons  of  manure  together,  could  not  evi¬ 
dently  increase  the  yield  as  25.6  tons  per  acre  was  the  limit  of  which 
this  soil  seemed  capable. 

Although  the  highest  yield  was  from  Plat  4,  with  nitrate  alone,  this 
is  probably  a  trifle  more  than  should  be  due  to  the  nitrate,  as  a  study 
of  residual  effects  during  the  next  two  years  seems  to  show  that  the 
soil  conditions  of  this  plat  were  slightly  more  favorable  than  those  ad¬ 
jacent. 

The  results  from  the  two  complete  fertilizers,  Plats  9  and  10,  are 
disappointing  in  yield.  The  highest  yield  was  obtained  from  th6  one 
containing  the  larger  quantity  of  nitrate  of  soda,  100  pounds,  produ- 


FERTILIZER  EXPERIMENTS  WITH  SUGAR  BEETS. 


7 


cing  1.7  tons  more  than  the  other  with  fifty  pounds.  It  is  very  likely 
that  the  increase  in  Plat  10  was  not  entirely  due  to  the  larger  quantity 
of  nitrate  in  the  complete  fertilizer,  as  the  yields  from  these  plats 
during  the  next  two  years  seem  to  show  that  the  soil  on  Plat  10  had 
greater  producing  capacity  than  the  adjacent  No.  9.  When  it  is 
considered  that  the  two  complete  fertilizers  contained  nearly  the 
same  amount  of  nitrogen,  the  less  nitrate  in  one  being  balanced  by 
more  dry  blood  in  the  other,  and  that  the  average  yield  of  the  two 
plats  is  the  same  as  the  unfertilized  plat,  it  is  hard  to  ascribe  any 
effect  at  all  upon  the  yi&d  due  to  the  nitrogen  in  the  complete  fertil¬ 
izers.  The  curious  fact  appears  here  in  the  complete  fertilizers, 
as.  well  as  during  the  tests  of  the  next  two  years,  that  phosphoric 
acid  and  potacli  in  the  presence  of  nitrogen  on  our  soils  seems  to  neu¬ 
tralize  to  a  great  extent  the  beneficial  effect  of  the  nitrogen  upon  the 
yield  when  compared  with  the  results  from  nitrogen  used  alone. 

In  the  results  from  this  experiment  the  highest  sugar  content 
and  purity  are  associated  with  the  lowest  yields,  the  highest  being 
found  in  the  lowest  yielding  plat,  No.  9,  with  the  complete  fertilizer, 
and  the  lowest  sugar  content  in  the  highest  yielding  plat,  No.  4, 
with  nitrate  of  soda,  with  the  exception  of  the  one  with  excessive 
quantity  of  manure. 

In  this  test  also  the  phosphate  form  the  bone  meal,  although  in¬ 
effective  upon  the  yield  when  used  alone,  with  nitrate  it  seemed  to 
a  great  extent  to  prevent  the  lowering  of  sugar  content  and  purity, 
the  nitrate  and  bone  meal  plat  giving  the  highest  yield  of  sugar  per 
acre  of  any  plat  in  the  series,  while  the  one  with  the  excessive  quan¬ 
tity  of  manure  produced  the  least,  the  unfertilized  plat  giving  the 
next  lowest  amount  of  sugar  per  acre. 

FERTILIZER  EXPERIMENTS  IN  1904 

On  Field  C3. — The  fertilizer  experiment  for  this  season  was 
planned  to  include  a  series  of  all  three  elements,  used  in  about  the 
proportion  which  experiments  elsewhere  had  proven  to  be  fair  average 
quantities.  As  nitrate  bone  meal  had  shown  only  negative  results  the 
previous  year,  acid  treated  phosphate  rock  or  superphosphate  as  the 
source  of  the  phosphoric  acid  was  used,  and  this  season  it  was  planned  to 
give  a  more  thorough  test  with  nitrate  of  soda  which  had  given 
the  best  results  in  1903.  The  same,  as  well  as  twice  the  amounts 
used  in  1903  were  given  in  one  application  at  the  time  of  planting, 
and  also  in  three  applications.  High  grade  sulphate  of  potash 
was  employed  as  a  source  of  the  potash.  Refuse  lime  cake  from 
the  sugar  factory  was  also  used  on  one  plat.  This  is  the  refuse 
lime  which  has  been  used  in  refining  and  purifying  the  juices 
in  sugar  making,  and  contains  a  small  proportion  of  phosphoric 
acid  and  nitrogen,  large  quantities  of  which  are  used  as  a  fertilizer 
on  the  sugar  beet  soils  of  Germany  and  it  was  thought  it 
might  have  some  effect  upon  our  soils.  Such,  however,  proved 
not  to  be  the  case.  The  thoroughly  air  dried  lime  cake  was 


8 


BULLETIN  115. 


scattered  over  the  land  at  the  rate  of  4.7  tons  per  acre  and  thoroughly 
harrowed  into  the  soil  three  times  before  seeding. 


The  following  analysis  of  lime  cake  is  given  in  the  Beet  Sugar 
Gazette  of  July  20,  1903: 

Per  Cent 

Potash.. _ _ _ _ _ - . . . 05 

Phosphoric  Acid . . . . - - . - - - — -  2.08 

Nitrogen - - - - — - . — - . .  .26 

Lime  Carbonate - - - - - - 54.61 

Oxide  of  Lime.. _ _ _ - . - . - - - 13.32 


The  fertilizers  were  applied  at  the  time  of  seeding  with  the  seed, 
by  the  use  of  an  attachment  to  the  regular  seed  drill.  The  fertilizer 
falls  in  such  a  way  that  a  slight  layer  of  soil  falls  over  the  seed  and  the 
fertilizer  over  this  layer  and  a  thicker  layer  of  soil  covers  fertilizer 
and  all.  It  will  be  seen  that  in  this  way  a  large  amount  of  concen¬ 
trated  chemicals  is  applied  directly  with  the  seed.  The  beet  seed  has 
germinated  quicker  and  stronger  when  applied  with  the  fertilizer  in 
this  way  than  when  no  fertilizer  was  used.  As  all  the  materials  were 
easily  soluble  examination  showed  that  it  had  been  practically  ab¬ 
sorbed  by  the  moist  soil  in  a  few  days  before  germination  of  the  seed 
was  fairly  in  progress.  The  method  of  applying  fertilizers  with  a 
drill  was  changed  also  because  it  was  realized  that  should  fertilizers 
be  found  desirable  to'usesto  any  extent  on  sugar  beets,  the  cheapest 
method  of  practice  would  be  the  most  desirable. 

It,  was  planned  to  apply  the  materials  used  singly  or  in  mixture 
in  the  following  quantities: 

Nitrate  of  soda  150  pounds,  and  the  same  quantity  in  three  ap¬ 
plications  of  fifty  pounds  each,  one  portion  applied  at  time  of  seeding, 
and  the  other  two  portions  at  different  periods  later  in  the  season. 

Nitrate  of  soda  300  pounds,  and  in  the  same  quantity  in  portions 
of  100  pounds  each  in  three  applications,  as  before. 

Acid  phosphate  rock,  300  pounds. 

Sulphate  of  potash,  100  pounds. 

However,  it  was  found  that  the  three  materials  differed  in  tex¬ 
ture  and  consistency,  no  two  mixtures  being  alike,  it  was  impossible 
to  regulate  the  drill  attachment  to  sow  the  exact  quantity  intended. 

Soil  History  of  Field  C3,  1904. — The  most  practical  benefit  from 
the  results  of  an  experiment  of  this  kind  would  doubtless  be  derived  if 
carried  out  on  soil  which  had  been  more  or  less  exhausted  by  previous 
beet  crops,  but  none  such  was  available. 

The  land  finally  chosen  was  some  which  had  borne  alternate 
crops  of  grain  and  corn  for  the  previous  five  years  without  manure, 
and  had  not  been  in  alfalfa  for  at  least  ten  years,  as  far  as  known. 
On  such  a  soil  it  would  be  natural  to  expect  that  the  nitrogen  would 
be  nearly  exhausted,  and  the  high  return  from  the  nitrogen  in  the 
fertilizer  is  not  surprising. 

The  previous  crops  on  Field  C3  for  ten  years,  as  far  as  known, 
have  been  as  follows:  1893  red  clover;  1894  barley,  rye  and  oats; 
1895  corn;  1899  grain;  1900  corn;  1901  emmer;  1902  Kaffir  corn;  1903 
wheat;  1904  beets,  fertilizer  experiment, 


FERTILIZER  EXPERIMENTS  WITH  SUGAR  BEETS.  9 

The  land  was  plowed  in  the  spring  and  prepared  for  planting  in 
the  usual  way.  The  seed  used  was  Kleinwanzlebener  grown  in  the 
otate  of  Washington,  planted  at  the  rate  of  thirty  pounds  per  acre 
with  the  fertilizer  applied  April  27.  A  heavy  rain  occurred  from  April 
30  to  May  3,  amounting  to  four  inches,  and  had  the  result  of  forming 
a  thick  crust  on  the  surface,  making  it  very  difficult  for  the  germina¬ 
ting  seed  to  break  through.  This  was  assisted  somewhat  by  the  use 
of  a  roller,  but  the  final  result  was  that  although  uniform  the  stand 

of  beets  was  rather  thin,  with  a  distance  of  12  to  15  inches  between 
beets  after  thinning. 

On  Plats  8  and  9  the  first  top  dressing  of  nitrate  of  soda  was 
applied  June  11,  and  the  second.  July  29.  All  the  plats  which  had 
received  nitrate  of  soda  alone  or  in  combination  were  in  better  grow¬ 
ing  condition,  July  15,  with  greener,  larger  leaves  than  those  without 
it,  except  Plat. 11,  where  the  action  of  nitrate  was  only  slightly  appar- 
ent.  This  thrifty  appearance  was  in  about  the  proportion  in  which 
the  nitrate  had  been  used.  This  difference  in  appearance  continued 
until  harvest. 

The  beets  were  weeded  by  hand  and  cultivated  and  irrigated 
three  times,  samples  for  analysis  taken  on  October  15,  and  plats  har¬ 
vested  October  15,  16  and  17. 

Table  9. 

FERTILIZERS  ON  FIELD  C3,  1904 — ONE-TENTH  ACRE  PLATS — PLANTED 


APRIL  27 


Plat  Number 

Total  Am’t  of  Ferti¬ 

lizer  used  per  acre 

£ 

KIND  OF  FERTILIZER 

Per  Acre 

Cost  of  Fertilizer 
per  acre 

lield  of  Clean  Beets 
per  acre 

Sugar  in  Beets 

- — : — - — 

Purity  Coefficient 

Am’t  Received  per 
acre  for  Beets 

Am’t  Received  Less 
Cost  of  Fertilizer 

1 

Pounds 

240 

...  Pounds 

Nitrate  of  Soda .  14.1 

Sulphate  of  Potash .  96 

$  7.34 

Tons 

14.75 

per  ct. 
16.8 

89.1 

$73.75 

$66.41 

2 

128 

- — - — — 

Sulphate  of  Potash .  128 

4.03 

12.60 

15.3 

86.6 

63.00 

58.97 

3 

435 

Sulphate  of  Potash . 109 

Acid  Phosphate  Rock .  326 

6.69 

12.77 

15.3 

88.8 

63.85 

57.16 

4 

330 

Acid  Phosphate  Rock . 330 

3.30 

11.53 

14.6 

86.2 

57.65 

54.35 

5 

495 

Acid  Phosphate  Rock .  330 

Nitrate  of  Soda .  165 

8.25 

14.94 

14.3 

“lSdP 

89.0 

74.70 

66 . 45 

6 

No  Fertilizer . 

10.98 

87.9 

54.90 

54.90 

7 

140 

JN  itrate  of  Soda .  140 

4.20 

13.16 

15.2 

88.0 

65  80 

61.60 

8 

187 

Nitrate  of  Soda .  97 

June  11 . 45 

June  29 .  45 

5.60 

13.92 

15.3 

86.1 

69.60 

64.00 

y 

431 

Nitrate  of  Soda .  m 

June  11 . 160 

July  29 . 160 

12.93 

15.30 

15.4 

88.8 

76.50 

63.57 

10 

580 

Nitrate  of  Soda .  40 

(a)  June  11. . 160 

17.40 

15.30 

14.8 

85.5 

76.90 

59.50 

li 

578 

Complete  Fertilizer _ 

11.20 

11.72 

16.4 

89.0 

58.60 

47.40 

Nitrate  of  Soda . 153 

Acid  Phosphate  Rock . 315 

Sulphate  of  Potash . 195 

12 

9360 

Lime  Cake . 4  68  tons 

9.73 

15.8 

88.1 

48.65 

(air  dried) 

Average . 

U..  :  .  1 

13  06 

15.4 

87.8  1  65.30 

(a)  Applied  by  mistake. 


10 


BULLETIN  115. 


Comments  on  Results  of  Fertilizer  Experiment  1904. — The  most 
important  points  as  indicated  by  the  results  of  this  experiment  are 
the  higher  yields  wherever  nitrate  was  used  either  alone  or  in  combin¬ 
ation  except  where  used  in  the  “complete”  fertilizer.  There  is  noth¬ 
ing  to  indicate  that  there  was  any  benefit  from  applying  the  same 
amount  of  nitrate  in  several  doses.  In  the  case  of  Plat  8  the  higher 
yield  over  Plat  7  is  undoubtedly  due  to  the  larger  amount  used  in  the 
three  applications.  In  the  case  of  Plat  10  which  accidentally  received 
a  top  dressing  where  it  was  not  intended,  the  larger  total  quantity 
used  did  not  increase  the  yield,  although  it  lowered  the  sugar  content 
and  purity  slightly.  There  is  also  a  little  evidence  that  sulphate  of 
potash  had  some  effect  and  that  it  at  least  did  a  little  more  than  pay 
for  itself,  while  the  acid  phosphate  had  very  little  if  any  effect  upon 
the  yield.  It  is  also  seen  that  the  effect  of  nitrate  was  not  influenced 
by  potash  or  the  acid  rock  when  used  separately  with  nitrate,  but 
when  all  three  were  used  together  in  the  complete  fertilizer,  the  re¬ 
sult  is  negative,  as  was  found  in  the  experiment  of  the  previous  year. 
Looking  at  this  result  in  oneway  there  seems  to  be  a  neutralization  of 
the  action  of  nitrate  in  presence  of  potash  and  phosphate  together. 

The  limit  of  the  most  profitable  application  of  nitrate  of  soda 
with  the  soil  and  conditions  of  this  experiment  appears  to  be  about 
175  pounds.  Taking  into  consideration  all  the  plats  where  the  in¬ 
creased  yield  seems  due  to  a  reasonable  quantity  of  nitrate  a  moder¬ 
ate  estimate  would  be  that  on  land  capable  of  producing  11  to  15  tons 
without  fertilizers,  the  profit  can  be  increased  from  $9  to  $10  per 
acre  by  the  use  of  said  amount  of  nitrate  of  soda.  The  larger  quanti¬ 
ties,  even  the  extreme  amount  of  580  pounds,  although  giving  a  profit 
above  the  cost  of  application,  did  not  give,  returns  in  proportion  to 
the  amounts  used,  after  deducting  the  cost. 

The  results  of  the  lime  cake  applied  was  ineffective  if  it  did 
not  actually  decrease  the  yield.  In  this  experiment  there  is  no  indi¬ 
cation  to  show  that  phosphoric  acid  used  with  nitrate  of  soda,  in¬ 
creased  the  sugar  content  of  the  beet  over  nitrate  alone,  as  in  the 
experiment  of  the  previous  year.  If  anything,  this  effect,  is  due  to 
potash  with  nitrate,  in  this  experiment. 

The  sugar  content  and  purity  is  generally  uniform  and  satisfac¬ 
tory,  being  the  highest  on  Plat  1  with  nitrate  of  soda  and  potash,  and 
Plat  11  with  all  the  elements.  In  this  experiment,  perhaps  for  the 
reason  that  the  average  yield,  thirteen  tons,  of  all  the  plats  is  below 
the  average  of  this  district,  there  is  no  connection  between  higher 
yields  and  high  sugar  content  and  purity,  or  vice  versa. 

FERTILIZER  EXPERIMENTS  IN  1905 

The  experiment'  this  season  with  fertilizers  of  sugar  beets  was 
conducted  on  a  large  area,  and  in  cooperation  with  a  farmer  growing 
beets  exclusively  and  under  his  control  as  regards  cultural  methods. 
The  experiment  can  therefore  be  considered  as  under  the  conditions 
of  ordinary  farm  wrork,  and  none  of  the  refinements  possible  in  small 
plat  work  was  attempted,  with  the  exception  of  the  accurate  appli- 


FERTILIZER  EXPERIMENTS  WITH  SUGAR  BEETS. 


11 


cation  of  the  fertilizers  and  weighing  the  beets  from  each  plat  separ¬ 
ately.  Ihe  weights  and  tare  were  taken  at  the  factory  in  exactly  the 
same  manner  and  in.  the  regular  way  all  beets  are  received. 

A  sufficient  number  of  average  beets  were  taken  from  each  load 
as  delivered,  or  about  six  per  load,  to  make  a  total  sample  of  eighteen 
beets  per  plat  for  analysis  as  to  sugar  content  and  purity.  The  only 
reason  for  the  analysis  and  taking  samples  in  this  manner  was  to  de¬ 
termine  whether  any  of  the  beets  as  delivered  would  be  unsatisfac¬ 
tory.  JNo  other  comparisons  can  be  made  as  to  the  analysis,  as  there 
was  several  weeks  difference  m  the  time  of  harvesting  the  various 
plats  and  also  m  exposure  to  the  drying  influences  of  the  air,  the  beets 
having  been  dug  and  placed  in  piles. 

,  difference  between  results  from  the  various  fertilizers,  when 

the  experiment  is  conducted  in  this  manner  must  be  rather  great  to 
be  oi  value,  but  when  large  should  be  convincing.  The  results  how- 

ever,  only  corroborate  those  trials  made  in  previous  years  on  smaller  areas. 

ihe  location  of  this  tract  is  about  one  quarter  of  a  mile  from  the 
grounds  where  the  previous  tests  reported  were  made,  and  appar¬ 
ently  of  the  same  character,  if  anything  more  productive.  The  field 
where  the  experiment  was  conducted  was  ideal  in  location  and  slope 
being  very  uniform  of  surface,  smooth,  with  just  sufficient  grade  to 
facilitate  uniform  flow  of  water  in  irrigation.  The  plats  weie  made 
ong  in  proportion  to  width,  a  point  of  great  value  in  comparative 
tests  each  plat  occupying  twelve  rows,  twenty  inches  apart,  or  nearly 
twenty  feet  wide  to  1240  feet  or  nearly  a  quarter  of  a  mile  long,  and 
t  lerefoie  nearly  sixty-three  times  as  long  as  wide.  The  average  area 
ot  the  plats  was  six-tenths  acre  to  each  plat. 

•i  exPeijiment  1S  considerable  value  for  the  reason  that  this 
soil  had  already  previously  produced  three  successive  crops  of  sugar 
beets,  the  experimental  crop  being  the  fourth,  and  without  manure 
on  the  portion  where  the  plats  were  located,  except  on  a  small  strip 
running  across  all  the  plats  at  one  end,  where  manure  had  been  used 
tor  two  years.  This  test  is  of  particular  value  because  fertilizers,  if 
effective,  are  needed  when  the  soil  is  becoming  exhausted  by  succes¬ 
sive  crops  of  sugar  beets.  The  returns  from  unfertilized  and  un¬ 
manured  plats  are  disappointing  for  the  purpose  of  the  experiment 
by  too  high  yields,  for  the  various  elements  in  the  fertilizers  do  not 
Have  an  opportunity  to  demonstrate  what  each  element  can  really  do 
on  exhausted  beet  soil.  That  the  soil  was  not  exhausted  is  well  seen 
It  also  shows  the  staying  qualities  of  our  Colorado  soil  with  a  pre¬ 
sumably  exhausing  crop.  1 

The  land  had  previously  been  in  alfalfa  for  a  number  of  years, 
with  a  crop  of  wheat  succeeding  the  alfalfa,  and  before  the  first  crop 
of  beets  as  follows:  1900  alfalfa,  of  several  years  standing:  1901 
wheat;  1902  sugar  beets,  1903  sugar  beets;  1904  sugar  beets,  175 
tons  per  acre,;  1905  sugar  beets,  as  reported  in  this  experiment, 
ihe  average  yield  on  twenty  five  acres,  including  the  fertilizer  ex¬ 
periment,  and  balance  of  manured  land  in  1905,  was  nearly  16.5  tons 
per  acre. 


12 


BULLETIN  115. 


The  fertilizer  used  and  the  quantities  of  each  intended  for  ap¬ 
plication,  alone  and  in  combination  are  as  follows: 

Nitrate  of  soda,  200  pounds  and  400  pounds. 

Sulfate  of  potash  (high  grade)  100  pounds 

Acid  bone  meal,  200  pounds. 

Acid  bone  meal  was  stated  to  have  been  made  up  In  proportions 
as  follows: 

1800  pounds  steamed  bone  meal. 

750  pounds  50  Beaume  sulphuric  acid. 

All  the  fertilizers  were  passed  through  a  one-fourth  inch  sieve 
and  well  mixed  in  the  proportion  desired.  The  land  was  plowed  in 
the  spring  and  prepared  for  planting  in  the  usual  way,  which  was 
done  on  May  1-2,  sowing  the  fertilizer  along  with  the  seed  by  an  at¬ 
tachment  to  the  beet  drill,  approximating  very  closely  the  total 
amount  desired  per  acre  of  each  ingredient.  The  seed  used  at  the 
rate  is  sixteen  pounds  per  acre  was  the  German  imported  Klein- 
wanzlebener  supplied  by  the  sugar  factory.  As  before  noted  the 
seed  germiniated  quicker  and  stronger  on  the  fertilized  than  the  un¬ 
fertilized  plats.  Even  the  large  quantity  of  426  pounds  per  acre 
sodium  nitrate  with  the  seed  had  no  injurious  effect  upon  the  ger¬ 
mination.  The  beets  were  hoed  and  thinned  once,  and  cultivated 
and  irrigated  three  times  each.  The  two  plats  of  nitrate  of  soda 
alone,  especially  the  larger  quantity,  were  distinguished  by  thrifty 
growth  throughout  the  season,  the  larger  quantity  having  apparently 
twice  as  large  tops  and  much  larger  sized  beets  than  any  other  plat. 

The  harvest  began  October  24  and  was  finished  November  29. 
Two-thirds  of  Plat  11  was  weighed  October  26,  and  the  balance  No¬ 
vember  13,  for  the  reason  that  a  snowstorm  set  in  just  as  harvesting 
began,  followed  by  a  freeze,  the  temperature  falling  to  eight  below 
zero.  The  fields  were  protected  by  the  fallen  snow  and  no  injury 
resulted  only  that  harvesting  was  delayed  ten  days.  When  digging 
could  be  resumed,  another  freeze  being  feared,  all  the  beets  were 
plowed  out  as  fast  as  possible,  progressing  from  Plat  11  towards 
Plat  1.  They  were  placed  in  piles  and  covered  with  tops.  It  thus 
occurred  that  Plats  4  to  1  inclusive  were  weighed  without  much  loss 
or  shrinkage,  and  Plats  5  to  10  inclusive,  probably  suffered  consider¬ 
able  loss  through  shrinkage,  some  of  the  beets  being  exposed  over 
three  weeks  before  being  weighed.  These  facts  must  be  considered 
in  comparing  results. 

Comments  on  Result  of  Fertilizer  Experiment  in  1905. — The  most 
striking  items  of  consideration  in  the  experiment  of  1905  are  that  the 
unfertilized  plats  gave  the  lowest  yields  in  the  series,  and  on  an  aver¬ 
age  those  containing  nitrogen  the  highest.  Some  allowance  must  be 
made  for  the  fact  that  Plats  1  to  3  gave  nearly  as  high  yields  as  those 
containing  nitrate,  as  all  the  conditions  were  in  favor  of  Plats  1  to  3 
showing  greater  weights,  being  harvested  and  weighed  from  two  to 
three  weeks  later  than  the  balance  of  the  plats  which  were  being  ex¬ 
posed  to  shrinkage  during  that  time. 

There  are  also  two  discrepancies  in  the  fact  that  while  phosphate 


FERTILIZER  EXPERIMENTS  WITH  SUGAR  BEETS.  13 

and  potash,  all  conditions  being  considered,  gave  very  small  increase 
when  used  singly,  the  two  used  together  produced  higher  yield  than 
either  alone;  the  other  being  the  small  yield  of  Plat  7  where  the  smal¬ 
ler  quantity  of  nitrate  was  used  alone,  when  compared  with  other 
plats  containing  nitrate. 


Table  10 

FERTILIZERS  ON  THE  ANDREWS  FARM  SOUTH~OF  LAKE  PARK,  1905 _ 

SIX-TENTH  ACRE  PLAT 


J  Plat  Number 

KIND  OF  FERTILIZER 

Per  Acre 

Cost  of  Fertilizer 
per  acre 

Yield  of  Clean  Beets 

per  acre 

Sugar  in  Beets 

Purity  Coefficient 

Amount  Received  per 

acre  for  Beets 

Amount  Received  Less 

Cost  of  Fertilizer 

Factory  Tare  was  - 
© 
a 

Av.  Wt.  of  18  Sam-  m 
pie  Beets  per  Beet  § 

1 

. , _  Pounds 

Acid  Bone  Meal .  193 

8  1.93 

Tons 

15.61 

per  ct 
15.2 

87.8 

$78.05 

$76.12 

10. 

31 

2 

Acid  Bone  Meal .  192 

Sulphate  of  Potash .  96 

5.58 

16.81 

15.4 

88.0 

84.05 

78.47 

10. 

28 

3 

Sulphate  of  Potash .  \i> 

4.47 

15.14 

15.0 

86.2 

75.70 

71.23 

10.8 

29 

34 

4 

Sulphate  of  Potash .  100 

Nitrate  of  Soda .  199 

9.12 

17.89 

14.2 

85.8 

89.45 

80.33 

12.0 

5 

Nitrate  of  Soda .  426 

12.7S 

18.60 

14.6 

85.7 

93.00 

80.22 

9. 

26 

6 

No  Fertilizer . 

14.76 

14.0 

87.2 

73.80 

73.80 

14. 

24 

7 

Nitrate  of  Soda .  op 

6.36 

16.16 

15.0 

85.3 

80.80 

74.14 

10. 

~2T 

8 

Nitrate  of  Soda .  214 

Acid  Bone  Meal .  215 

9.28 

15.93 

14.71 

15.2 

85.3 

79.65 

70.37 

15. 

15. 

24 

9 

Complete  Fertilizer . 

Acid  Bone  Meal .  187 

Nitrate  of  Soda .  187 

Sulphate  of  Potash  .  94 

11.06 

15.0 

86.3 

73.55 

62.49: 

10 

No  Fertilizer  . 

12.18 

15  2 

84.9 

60.90 

60.90 

13.2 

18 

11 

No  Fertilizer . 

13.63 

15.2 

88.7 

68.15 

68.15 

8.6 

30 

Average .  1 

15.58 

14.9! 

86.5 

$77.90 

27 

The  effect  of  complete  fertilizer  although  more  favorable  than 
in  the  previous  two  years,  indicates  the  same  general  tendency,  in 
the  apparent  neutralization  of  the  action  of  nitrate  of  soda  in  the 
presence  of  potash  and  phosphoric  acid  together,  as  derived  from 
the  fertilizer;  the  yield  being  about  the  same  as  the  unfertilized  plat, 
two  plats  removed,  less  than  the  nitrate  and  acid  bone  meal  plat  ad¬ 
joining,  but  much  more  than  the  unfertilized  plats  adjoining  on  the 
other  side. 

All  the  results  seem  to  indicate  that  the  increase  in  yields  was 
chiefly  due  to  nitrate  of  soda  used  alone  or  with  the  other  elements, 
and  that  there  was  no  additional  net  profit  from  the  application  of 
over  double  the  quantity  of  the  smaller  amounts. 

Taking  all  the  factors  into  consideration  a  careful  comparison 
of  Plats  5  and  6  and  conservative  estimates  seem  to  indicate  that  on  soil 
capable  of  producing  from  13.5  to  14.5  tons  per  acre  without 
fertilization,  about  200  pounds  of  nitrate  of  soda  caused  a  gross  in¬ 
crease  of  $20  per  acre  with  beets  at  $5  per  ton,  or  a  net  increase  over 
the  cost  of  fertilizer  of  about  $6  to  $7  per  acre. 

In  appearance  the  size  and  shape  of  the  beets  grown  in  this  ex- 


14 


BULLETIN  115 


periment  were  excellent,  the  average  weight  per  beet  of  the  200  sam¬ 
ples  being  twenty-seven  ounces,  or  1.7  pounds. 

The  sugar  content  and  purity  of  the  beets  analyzed  were  in  gener¬ 
al  satisfactory,  and  about  as  high  as  the  average  of  the  district  this 
season  (1905).  Both  the  sugar  content  and  yield  of  sugar  beets  were 
somewhat  below  the  average  of  previous  seasons  in  Northern  Colo¬ 
rado  and  elsewhere,  largely  due  to  the  late  spring  and  copious  rains  in 
the  earlier  part  of  the  growing  season,  which  caused  a  more  luxur¬ 
iant  growth  of  tops  or  leaves  than  usual,  but  which  proved  rather  un¬ 
favorable  to  the  production  of  a  proportionate  increase  in  weight  of 
the  sugar  beet  crop. 


RESIDUAL  OR  AFTER  EFFECTS  OF  MANURES  AND  FERTILIZERS 

Experiments  on  Field  F,  1903-4-5. — From  the  plats  on  Field  F, 

to  which  manures  and  fertilizers  were  applied  in  1903,  the  data  of 
which  is  given  in  Table  5,  the  beets  were  harvested  separately  and 
other  data  secured  in  the  following  two  years  in  order  to  determine 
the  residual  or  after  effects  of  the  manures  and  fertilizers  used.  Some 


very  interesting  facts  were  disclosed,  that  data  being  given  in  Table 

11. 

Table  11. 

RESIDUAL  ON  AFTER  EFFECTS  OF  MANURE  AND  FERTILIZERS  APPLIED 

ONE  YEAR  ONLY  ON  FIELD  F,  1903 


so 

CD 

p 

3 

o' 

cd 

1-5 


1 

77 

3 


_6_ 

7 


KIND  OF  FERTILIZER 
Applied  in  1903  only 


I 


Amt.  per  acre — Tons 
Cow  Manure . 60 

Cow  Manure . 30 


Cow  Manure . 15 

Pounds 

Nitrate  of  Soda . 1'0 


10 


Nitrate  of  Soda . 1  0 


N  itrate  of  Soda . 10 

Raw  Bone  Meal . 200 


No  Fertilizer. 


Raw  Bone  Meal . 200 

Thomas  Phosphate..  ..400 
(or  Basic  Slag) _ 

Complete  Fertilizer . 

Nitrate  of  Soda . 50 

Dried  Blood . 75 

Acid  Bone  Meal . 250 

Sulphate  of  Potash. CO 
Carbonate  of  Potash. 75 
(from  Tobacco  Ashes) 


Complete  Fertilizer . 

Nitrate  of  Soda . 10" 

Dried  Blood . 25 

Acid  Bone  Meal . >50 

Sulphate  of  Potash.. f0 
Carbonate  of  Potash. 75 
(from  Tobacco  Ashes) 


Averages. . . . 


Yield  in  Tons  per  acre 


1903 


1904 


1905 


> 

< 

CD 

rs 

P3 

dQ 

CD 

cc 

HCJ 

CD 

33 

(X 


Quality  of  Beets 


1903 


C/2 

£ 

£2 

rj 


cd 

CD 

CD 


y 

1 

c+- 

z** 

a 

o 

CD 

35 


24.  V 


25.10 


25 . 25 


25.67 


25.61 


21.46 

21.72 


22.60 

20.63 


22.3. 


23.4., 


19.68  15.82 


20.3 1 
19.13 


16.94 

16.17 


15.55 


14.57 


14.57 

16.94 


17.78 


16.10 


17.07 


16.  D 


! per  ct 


"3  cc. 

2 

CD 

CD 

— t- 

lbs 


19.87  13.1  j81. 0  2.44 
82. "|2. CO 


19.99 


20.44 


14.3 


14.4 


20.91  13.3 


19. »y 


lb. 49 


18.01 


17.59 


14.61 

15.18  i6.79 


14.9 


15.1 

15.1 


15.1 


84.211.51 


83.3 


2.56 


83.8  2.03 


b5 .0 

87.3 


84.4 


16.1  87.9 


16.49  15.99  18.2"  14.6  84.4 


17.59 


16.02  19.01 


2.04 
2  23 


2.13 


1.59 


2  12 


X 

CD 

-i 

C 

CD 


o 

x 

X 


14.6  84.4,2.06 


j47 

51 


46 


47 


33 

31 

37 


42 


45 


1904 


45.3 


cc 

P 

TQ 

3= 

i-s 


X 

CD 

CD 


p.  C 

io .  2 


X 

p 

“J 


o 

o 

CD 

tts 


15.8 
15  9 


14.9 


16.2 


15 _8 
6  0 


14.4 


15.2 


15.0 


15.4 


2- 


—  CD 
‘  CT 

X^ 

v 

CD 

— t 

lbs 

2.13 


X 

CD 

r-j 

O 

CD 


H 

o 

w  I  : 


1905 


c 

U 

CD 

.-t- 

3  » 
3  -i 

M.  I 


84.3  2.13  41  4 
85.0  1.18,42.3 
28.1 


86.3 


87.4 

8675 


87.6 

8775 


87.3 

8771 


84.3 


86.3 


1.33, 


1.18  37. 


i. 13^9.7 


1.0440b 


1.22  38.1 


1.32  39.6 


1.23 


42.6 


1.08  40.8 


1.23 


39.0 


FERTILIZER  EXPERIMENTS  WITH  SUGAR  BEETS.  15 

Some  facts  as  to  the  effects  of  cow  manure  will  be  especially  in¬ 
teresting.  A  positive  residual  effect  is  noted  the  second  year.  'The 
difference  between  the  manured  plats  and  the  other  plats  which  had 
received  more  of  less  ineffective  fertilizers  was  even  more  largely  in 
favor  of  the  manure  the  second  year,  than  the  year  of  its  application. 
For  instance  the  difference  between  the  averages  of  the  three  manured 
Plats  1,  2  and  3,  and  the  unfertilized  or  ineffectively  fertilized  Plats 
6,  7  and  8  in  1903,  the  year  of  application,  was  3.2  tons  and  the  sec¬ 
ond  year  3.5  tons,  in  favor  of  the  manure. 

In  the  third  year  after  application  the  residual  effects  entirely 
disappeared  in  the  case  of  the  cow  manure,  the  difference  in  fact  be¬ 
tween  the  plats  just  given,  being  a  small  fraction  or  0.16  tons  against 
the  manure. 

While  there  are  interesting  after  effects  the  second  year  of  the 
application  of  manure,  the  yields  are  not  proportionate  to  the 
amounts  used  in  the  previous  year,  being  only  slightly  more  with 
sixty  and  thirty  tons  than  with  fifteen  tons. 

Thus  if  the  cost  and  the  expense  of  the  application  are  deducted, 
there  is  little  if  any  net  profit  from  the  increased  yield  of  sugar  beets  in 
the  year  of  the  application,  of  a  moderate  or  large  amount  of  manures, 
but  that  the  returns  are  found  in  the  succeeding  year  therefore  clear 
profit  except  for  the  expense  of  topping  and  delivery  of  the  ex¬ 
tra  quantity. 

It  is  also  seen  that  large  to  excessive  quantities  of  manure  used 
are  sheer  waste,  and  that  returns  as  good  if  not  better  are  obtained 
with  medium  amounts. 

In  the  case  of  ariy  residual  effect  from  nitrate  of  soda  where  it 
was  used  in  any  quantity  alone  or  with  potash  or  phosphoric  acid, 
leaving  out  its  use  in  Plat  3,  with  manure,  which  obscures  its  effects' 
in  Plats  4,  5  and  10,  on  the  face  of  the  returns,  there  actually  appears 
to  be  beneficial  after  effects,  although  this  is  probably  a  coincidence 
due  to  some  inherent  difference  in  the  quality  of  soil  on  these  plats 
for  it  would  be  almost  absurd  to  suppose  that  an  easily  soluable,  and 
in  the  soil,  unstable  compound  like  nitrate,  would  remain  until  a  second 
season. 

Comparison  of  the  sugar  content  of  the  beets  of  the  three  manured 
plats  and  the  unmanured  Plats  6,  7  and  8,  previously  mentioned, 
shows  a  difference  between  the  averages  the  first  year  of  1.7  per  cent' 
and  the  second  year  only  0.3  per  cent.  The  difference  in  yields  be¬ 
tween  the  two  was  greater  the  second  year  than  the  first,  but  of 
course  with  a  lower  average  yield  all  around.  The  purity  coefficient 
shows  a  difference  of  2.5  and  1.9  when  compared  in  the  same  way. 
The  point  of  the  whole  matter  is  that  in  the  second  year  the  sugar 
content  and  purity  of  the  beets  from  the  manured  plats,  with  higher 
yield,  was  just  about  as  good  as  that  of  the  unmanured  plats  with  low¬ 
er  yield,  which  was  not  the  case  the  first  year  the  manure  was  applied. 

Acknowledgements  for  furnishing  the  raw  materials  for  these 
experiments  are  due  Mr.  Wm.  S.  Myers,  of  the  Nitrate  of  Soda  Propo- 


16 


BULLETIN  115. 


ganda;  Armour  Fertilizer  Works,  Omaha;  German  Kali  Works,  New 
York;  and  Colorado  Packing  and  Provision  Company,  Denver. 

Relation  of  Size  and  Amount  of  Fresh  Beet  Tops  to  Quality  of 
Sugar  Beets. — In  the  samples  taken  for  analysis  in  all  the  fertilizer 
experiments  of  1903  and  1904,  the  beets  were  carefully  cleaned, 
weighed  and  the  tops  consisting  of  crown  and  leaves,  removed  in  the 
approved  manner,  and  beets  weighed  again.  Considerable  data  was 
then  secured  of  value,  especially  as  regards  the  amount  of  beet  tops, 
in  relation  to  the  size  of  the  beet,  quality  and  yield  and  fertilizers 
used.  The  detailed  data  is  given  in  Tables  12  and  13,  and  the  sum¬ 
mary  in  Table  14. 

Table  12.. 

DATA  AS  TO  THE  RELATION  OF  SIZE  AND  AMOUNT  OF  FRESH  TOPS  TO 


QUALITY  OF  SUGAR  BEETS,  1903 


1 

Plat 

Number 

Number 
of  Beets 
in 

Sample 

Average 
Weight 
Per  Beet 
in 

Pounds 

P^r  Cent 
Tops 

Sugar 

• 

m 

Beet 

1 

Purity 

Co¬ 

efficient 

2 

12 

2.17 

40 

15.6 

85.6 

3 

12 

3.13 

55 

15.0 

83.6 

FIELD  C 

4 

12 

2.25 

43 

15.1 

84.4 

Total  Area  Sampled 

5 

12 

2.46 

58 

14.8 

83.2 

0.6  Acres 

6 

12 

2.33 

52 

15.5 

85.4 

7 

12 

2.33 

46 

15.7 

86.4' 

\ 

Averages. . . 

72 

2.45 

49.2 

15.3 

84.7 

Field  F. — 1  Acre.. . . 

1 

12 

2.44 

72 

13.1 

81.0 

2 

12 

2.00 

47 

14.3 

82.8 

3 

12 

1.51 

51 

14.4 

84.2 

4 

12 

2.56 

46 

13.3 

83.3 

5 

12 

2.03 

47 

14.9 

83.8 

6 

12 

2.04 

33 

15.1 

85.0 

7 

12 

2.23 

31 

15.1 

87.3 

8 

12 

2.13 

37 

15.1 

84.4 

9 

12 

1.59 

42 

16.1 

87.9 

- 

10 

12 

2.12 

45 

14.6 

84.4 

Averages . 

120 

2.06 

45.3 

14.6 

84.4 

Field  E. — 0.2  Acres... . 

1 

12 

1.67 

41 

15.1 

87.3 

2 

12 

1.88 

44 

^15.3  7 

85.9 

- 

. 

vjr  1  si 

Averages 

24 

1.78 

42.5 

57 15.2  y 

86.6 

There  does  not  appear  to  be  any  definite  relation  between  these 
various  factors,  although  there  are  some  indications  that  the  larger 
beets  with  large  percentage  of  tops  have  somewhat  lower  sugar  con¬ 
tent  and  purity.  The  opposite  is  true  in  a  few  cases. 

Beet  tops  have  come  to  be  of  considerable  value,  being  pastured 
by  cattle  and  sheep  with  success.  The  value  of  the  beet  tops  thus 
pastured  has  a  market  price  at  present  of  from  $1.00  to  $3.00  an  acre 
and  sometimes  more.  As  to  palatibility  it  has  been  found  that  sheep 


FERTILIZER  EXPERIMENTS  WITH  SUGAR  BEETS. 


17 


will  readily  leave  alfalfa  hay  for  beet  tops,  but  that  the  crowns  are 
not  readily  eaten.  Cattle,  however,  will  eat  the  crowns  clean. 

Table  13. 

DATA  AS  TO  THE  RELATION  OF  SIZE  AND  AMOUNT  OF  FRESH  BEET  TOPS 


TO  QUALITY  OF  SUGAR  BEETS,  1904 


Plat 

Number 

Number 
of  Beets 
in 

Sample 

Average 
Weight 
Per  Beet 
Pounds 

1 

Per  Cent 
Tops 

1 

Sugar  in 
Beet 

Purity 

Co¬ 

efficient 

Field  C.3-Area  1.2  Acres 

1 

12 

1.28 

39.0 

16.8 

89.1 

2 

12 

1.12 

42.5 

15.3 

86.6 

3 

12 

1.29 

41.3 

15.3 

88.8 

4 

12 

1.42 

41.8 

14.6 

86.2 

5 

12 

1.70 

41.1 

14.3 

89.0 

6 

12 

1.44 

43.4 

15.6 

87.9 

7 

12 

1.58 

37.0 

15.2 

88.0 

8 

12 

2.24 

46.9 

15.3 

86.1 

9 

12 

1.93 

51.9 

15.4 

88.8 

10 

12 

2.66 

51.1 

14.8 

85.5 

11 

12 

1.28 

36.6 

16.4 

89.0 

12 

12 

1.23 

41.5 

15.8 

88.1 

Averages . . 

144 

1.60 

43.8 

15.4 

87.8 

Field  F. — Area  1  Acre—. 

1 

12 

2.13 

41.4 

15.2 

84.3 

2 

12 

1.18 

42.3 

15.8 

85.0 

3 

12 

1.33 

28.1 

15.9 

86.3 

4 

12 

1.18 

37.1 

14.9 

87.4 

5 

12 

1.13 

39.7 

16.2 

86.5 

6  - 

12 

1.04 

40.8 

15.8 

87.6 

7 

12 

1.22 

38.1 

16.0 

87.5 

8 

12 

1.32 

39.6 

14.4 

87.3 

9 

12 

1.23 

42.6 

15.2 

87.1 

10 

12 

1.08 

40.8 

15.0 

84.3 

Averages— . 

120 

1.23 

39.0 

15.4 

86.3 

Field  B. — Area  1  Acre.... 

w 

12 

1.92 

54.0 

14.6 

89.0 

N 

13 

1.57 

53.2 

13.9 

86.8 

1 

Averages. . .  | 

1 

26  | 

1.75  | 

| 

53.6  | 

| 

14.3  | 

87.9 

Table  14. 

SUMMARY  OF  AMOUNTS  OF  BEET  TOPS  AND  QUALITY  OF  SUGAR  BEETS 


FIELD 

Area  Acres 

Number  of 
Determinations 

Total  Nnmber 
of  Beets 
Analyzed 

Average  Weight 
Per  Beet 
Pounds 

Yield  of  Beets 

Per  Acre 

Tons 

Green 

►U 

H® 

co  2 

CD 

»  Pounds 

£  Per  Ton  of 

Beets 

Tops 

o  o  * 
•a  "•n 

GO  CD 

a 

rt 

Sugar  in  Beet 

Purity  Coefficient 

1903.. .  . . 

Cl 

0.6 

6 

73 

2.45 

27 

13.28 

984 

49.2 

15.3 

84.9 

1903 _ 

F 

1.0 

10 

120 

2.06 

23 

9.96 

906 

45.3 

14.6 

84.6 

1903 . . 

E 

0.2 

2 

24 

1.78 

20 

8.50 

850 

42.5 

15.2 

86.6 

1904. . . 

C3 

1.2 

12 

144 

1.60 

13 

5.70 

876 

43.8 

15.4 

87.8 

1904... . . 

F 

1.0 

10 

120 

1.23 

18 

7.02 

780 

39.0 

15.4 

86.3 

1904 . . . 

B 

1.0 

2 

25 

1.75 

22 

11.80 

1073 

53.6 

14.3 

87.9 

18 


BULLETIN  115. 


The  average  weight  per  beet  of  all  samples  analyzed  is  found  to 
be  1.76  pounds,  and  the  average  fresh  green  tops  44.2,  from  42  deter¬ 
minations  of  12  samples  each.  The  average  yield  of  19.8  tons  will 
thus  produce  8.75  tons  of  fresh  green  tops. 

The  loss  of  weight  in  thorough  air  drying  or  curing  has  not  been 
determined,  but  it  is  believed  that  one-eighth  of  the  green  weight 
would  be  a  reasonable  estimate.  Calculating  the  green  tops  at  44.2 
per  cent  of  the  net  weight  of  beets  the  relation  of  tons  per  acre  and 
tops  would  be  as  follows: 


Beets  per  acre 

Fresh  green  tops 

Estimated  Tons  air 

tons 

per  acre  tons 

weight  per  acre 

20 

8.84 

1.10 

15 

6.63 

.83 

10 

4.41 

.55 

Table  15. 

YIELD  OF  FRESH  BEET  TOPS  BY  GATHERING  AND  WEIGHING  ALL  THE 

TOPS  AFTER  HARVESTING  BEETS 


FIELD  F.  1904 — -ONE  TENTH  ACRE  PLATS, 


Yield  of  Beets 

Tops 

Tops  Per  Ton 

Per  Cent 

Plat  No. 

Per  Acre 

Per  Acre 

of  Beets 

Tops 

Tons 

Tons 

Pounds 

1 

19.57 

10.65 

1088 

54.4 

2 

20.23 

5.85 

578 

28.9 

3 

19.03 

5.88 

618 

30.9 

4 

19.20 

4.64 

484 

24.2 

5 

17.90 

5.11 

571 

28.5 

Note— Tops  on  Plats  2  to  5  were  allowed  to  remain  on  the  ground  from  three 
to  five  days  after  topping. 

The  data  given  in  Table  15  was  obtained  by  gathering  and 
weighing  all  the  tops  of  a  known  area,  with  yield  of  beets,  from  one 
to  five  days  after  topping.  A  considerable  per  cent  was  lost  in  this  way, 
being  impossible  to  gather.  There  was  also  considerable  loss  in 
weight  from  evaporation  in  those  last  gathered.  It  will  be  seen  that 
the  percent  of  tops  from  Plat  1  with  an  excessive  amount  of  leaves 
by  actually  gathering  all  the  tops,  is  greater  than  the  figure  obtained 
from  the  sample  beets,  the  sample  showing  forty-one  per  cent  and  the 
gathered  leaves  fifty-one  per  cent  of  the  beets  harvested. 

Data  in  Regard  to  Maturing  Period  of  Sugar  Beets. — The  data 
given  in  Tables  16,  17  and  18  was  obtained  in  cooperative  work  with 
the  Bureau  of  Chemistry,  Department  of  Agriculture,  Washington, 
D.  C.  All  the  analyses  of  1902  were  made  by  the  Bureau,  and  that  of 
other  years  in  the  laboratory  of  the  local  sugar  factory  by  the  courtesy 
of  Mr.  Booraem. 

The  samples  were  taken  every  week  beginning  with  the  last  week 
in  September  and  continuing  until  the  beets  were  all  harvested  or 
until  prevented  by  freezing  of  the  ground.  The  manner  of  taking 
the  samples  consisted  of  digging  all  the  beets  from  a  fifty  foot  row, 
each  successive  digging  adjoining  the  other,  counting,  cleaning,  par- 


FERTILIZER  EXPERIMENTS  WITH  SUGAR  BEETS.  19 

tially  topping,  weighing  the  beets  and  analyzing  twenty-five  average 
specimens.  .  In  the  samples  shipped  to  Washington  the  sugar  content 
and  purity  is  based  on  the  first  weight  of  the  beets,  thus  allowing  for 
evaporation  and  shrinkage.  The  weight  per  beet  and  estimated  yield 
pei  acre  is  a  little  higher  than  the  actual  for  the  reason  that  all  the 
crowns  were  not  removed  in  trimming.  The  difference  is  also  seen 
m  the  actual  yield  of  each  plat  when  harvested,  being  somewhat  less 
than  the  tonnage  from  the  samples. 


Table  16. 

SAMPLES  FROM  FIELD  D,  1902 


Date  of  Sampling 


September  17 
September  26. 

October  3  _ 

October  10  ... 
October  17  ... 

October  24 _ 

October  31 _ 

November  7  . 
November  14. 
November  21 
November  28. 
December  5  . 


Average- 


Mean  Weight  of 
Topped  Beets  in 


Ounces 

Pounds 

19 

.6 

1 

.23 

24 

.5 

1 

.53 

25 

0 

'  1 

.56 

27 

0 

1 

.69 

27 

4 

1 

.71 

22 

9 

1 

43 

27 

0 

1 

69 

22 

0 

1 

38 

23 

4 

1 

46 

26 

9 

1 

68 

26. 

1 

1 

63 

27. 

2 

1 

70 

24. 

9 

1. 

56 

Sugar  in 
Beet 

Per  Cent 

V 

Purity 

Co¬ 

efficient 

12.9 

80.5 

12.1 

78.3 

10.5 

74.0 

9.8 

66.6 

13.2 

81.4 

14.3 

83.8 

13.9 

80.4 

14.7 

87.0 

14.4 

84.3 

13.7 

78.0 

13.6 

79.1 

13.0 

79.7 

13.0 

79.4 

Estim  d 
Yield 
Per  Acre 
|  Tons 


20.2 

26.0 

25.7 

27.3 
24.2 

25.5 

31.8 

24.4 

26.6 
28.6 

26.7 

25.7 


26.0 


W  killing  frost.  Sept.  20-21,  6  inches  rain, 
i  leld  of  whole  Plat  when  harvested  was  25.4  tons 

Average  space  between  beets  9.3  inches  but  with  9%  of  the  beets  missing  the  majority 
Twe  8.56  inches  apart.  J  J 


Table  17. 

SAMPLES  FROM  FIELDS  F  AND  E,  1903 
Field  F.  Plat  6 


Date  of  Sampling 

»  ^ 

Mean  Weight  of 
Topped  Beets 

Ounces  |  Pound 

Est. Yield 
Per  Acre 
Tons 

Sugar  in 
Beet 
Per  Cent 

Purity 

Coeffi. 

September  26  ... 

October  6  .. 

October  10 

October  17. 

October  26 _ 

November  3 

Average.... 

19.8 

22.9 
23.5 

17.4 
25.1 

25.9 

22.4 

1.24 

1.43 

1.47 

1.09 

1.57 

1.62 

1.40 

20.4 

19.7 

24.2 

21.8 

22.2 
23.8 

22.0 

14.8 

16.7 

15.7 
18.5 
16.2 

15.9 

16.3 

82.0 

83.6 
81.1 

81.6 
85.3 
81.7 

82.5 

Yield  of  whole  plat  when  harvested  21.5  tons.  Spacing  8.2  inches 
Nov.  7.  Sugar  in  beet  15.1.-  Purity  85.0. 


20 


BULLETIN  115. 


(Table  17,  Continued.) 


On  Field  E  | 

September  26  U - - 

1.47 

23.5 

20.7 

13.8 

79.1 

October  6  _ 

1.40 

22.4 

21.2 

15 . 3 

sl .  5 

October  10 _ _ 

1.53 

24.5 

19.6 

15.6 

79.7 

October  17 _ 

1.45 

23.2 

22.8 

14.4 

80.4 

October  26 _ 

1.25 

20.0 

21.7 

16.2 

87.3 

November  3  _ _ 

1.67 

26.7 

25.3 

15.1 

77.6 

Average _ _ — . 

1.46 

23.4 

21.9 

15.1 

80.9 

Yield  of  whole  plat  when  harvested  19.8  tons.  Spacing  10.5  inches. 
Nov.  7.  Sugar  15.1%  Purity  87.3. 


Table  18. 


SAMPLES  FROM  FIELD  F,  PLAT  6,  1904 


Date  of  Sampling 

Mean  Weight  of 
Topped  Beets  in 

Ounces  |  Pounds 

Est. Yield 
Per  Acre 
•Tons 

Sugar  in 
Beet 
Per  Cent 

Purity 

Coeffi. 

September  22  - - - . 

October  12 - - - 

October  15 . . . . 

October  20*—- . — - - 

October  22- . . . - . . 

Average.— . . . 

16.2 

18.1 

16.0 

16.6 

16.8 

16.7 

1.01 

1.13 

1.00 

1.04 

1.05 

1.05 

17.6 
18.8 

16.7 

18.2 

17.8 

15.4 
16.2 

16.7 

15.8 

16.4 

16.1 

83.5 
88.4 
87.9 

87.6 
89.1 

87.3 

*  Average  of  12  samples. 

Yield  of  whole  plot  when  harvested  16.9  tons.  _ .  ^ 

Average  space  between  beets  8.9  inches. 

The  data  secured  offers  some  interesting  evidence  as  to  the  prog¬ 
ress  of  ripening  in  the  sugar  beet,  the  most  striking  being  the  com¬ 
paratively  slight  increase  in  sugar  content  and  purity,  or  yield,  after 
the  last  week  in  September. 

The  data  for  1902  is  especially  interesting,  showing  the  effects  of 
the  early  freeze  of  September  12  of  that  year,  which  destroyed  the 
leaves.  This  was  followed  in  a  week  by  a  heavy  rain  amounting  to 
six  inches,  causing  the  beets  to  put  forth  an  entirely  new  set  of  leaves. 
The  effect  of  the  renewed  growth  is  plainly  seen  in  the  great  decrease 
of  sugar  content  and  purity  reaching  the  minimum  twenty  days  after 
the  rain  on  October  10. 

PRACTICAL  SUGGESTIONS  AS  TO  THE  USE  OF  FERTILIZERS  ON 

SUGAR  BEETS  IN  COLORADO 

The  Kind  to  Use.— Nitrogen  is  the  only  element  which  has  proven 
of  practical  value  giving  decided  profit  over  the  cost  of  application. 
Its  use  in  the  form  of  nitrate  of  soda  with  potash  and  phosphoric 
acid  together  in  “complete”  fertilizers,  has  not  been  as  effective  in 
increasing  the  yield,  as  nitrate  used  alone.  On  the  contrary  there  are 
decided  indications  that  the  effect  of  the  nitrate  has  been  largely 
neutralized  when  so  used,  although  the  quality  of  the  beet  has  been 
good. 


fertilizer  experiments  with  sugar  beets. 


21 


# 

Although  nitrogen  from  nitrate  of  soda  has  been  effective  in  in¬ 
creasing  the  yield,  no  sufficient  comparaive  tests  have  been  made 
as  to  the  effect  of  nitrogen  from  the  less  soluble  organic  fertilizers 
such  as  dried  blood,  tankage,  or  cottonseed  meal.  It  is  probable  that 
the  same  amount  of  nitrogen  from  those  sources  would  be  less  effective 
although  this  is  offset  to  some  extent  by  the  fact  that  their  cost  is 
less  and  more  could  be  used. 

WHERE  AND  HOW  TO  USE  NITRATE  OF  SODA 

The  Soil. — It  is  probable  that  nitrate  of  soda  could  not  be  used 
profitably  on  soil  which  is  in  condition  to  produce  close  to  the  maxi¬ 
mum  yields  of  the  particular  locality  without  manures  or  fertilizers. 
It  also  must  be  understood  that  fertilizers,  no  matter  how  effective, 
will  never  take  the  place  of  proper  preparation  of  the  soil  and  care  of 
the  crop.  It  is  absolutely  necessary  that  the  soil  be  in  good  physical 
condition  in  order  to  enable  plants  to  use  the  plant  food  therein,  or 
added  to  it. 

For  our  conditions  the  most  satisfactory  practice  would  probably 
be  to  use  nitrate  of  soda  along  with  a  light  coating  of  manure.  The 
maximum  effect  of  both  would  be  secured  in  this  way. 

Depending  upon  conditions  it  will  require  a  yield  of  sugar  beets 
of  from  six  to  ten  tons  or  more  to  cover  cost  of  production.  No  land 
is  likely  to  be  planted  to  sugar  beets  which  will  not  produce  that 
much.  The  high  average  yields  are  in  the  neighborhood  of  twenty 
tons  per  acre.  The  profitable  application  of  nitrogenous  fertilizers 
then  will  probably  be  on  soils  which,  without  manure  or  fertilizers, 
will  range  in  yield  from  ten  to  fifteen  tons  per  acre. 

ANY  INJURIOUS  EFFECTS  OF  NITRATE 

The  Beet. — Our  Colorado  soils  and  climate  have  shown  an  ability 
to  produce  a  high  quality  of  beet  under  good  average  conditions. 
The  quality  of  the  beet  is  also  largely  controlled  by  the  proper  irri¬ 
gation.  Manures  are  chiefly  valuable  for  the  large  amount  of  nitrogen 
they  contain,  besides  the  humus,  and  it  has  been  shown  that  even  ex¬ 
cessive  quantities  of  manure  will  lower  the  sugar  content  only  from 
one  to  two  per  cent,  and  purity  two  to  four  per  cent.  Excessive 
quantities  of  nitrate  of  soda  will  do  the  same,  but  neither  is  recom¬ 
mended.  The  presence  of  more  active  nitrogen  than  the  plants  can 
use  lessens  the  yield. 

It  might  be  reasonable  that  as  active  nitrogen  acts  as  a  stimu¬ 
lant  it  will  induce  the  plants  to  absorb  so  much  of  the  other  available 
elements  in  the  increased  crop,  that  there  would  be  none  left  over 
for  the  next  crop.  Our  soils  contain  ample  supplies  of  both  potash 
and  phosphoric  acid  held  in  reserve,  which  are  constantly  being  liber¬ 
ated  or  made  available  in  the  soil,  and  of  lime  we  have  something  to 
spare.  • 

It  is  claimed  that  nitrate  of  soda  has  a  tendency  to  make  the  soil 
more  compact  or  less  easily  workable.  Even  if  such  is  the  case,  and 
it  has  not  been  observed  in  our  experiments,  it  is  difficult  to  see  how 


22 


BULLETIN  115. 


this  could  take  place  with  the  frequent  cultivation  and  hoeings  sugar 
beets  are  bound  to  receive.  Granting  that  there  is  some  truth  in 
both  claims  advanced,  the  soil  would  have  ample  time  to  recover 
during  the  rotation  with  other  crops,  which  is  imperative  for  best  all 
round  results.  It  is  well  known  that  crops  do  not  use  the  same 
amounts  of  food  elements,  and  while  growing  they  give  an  op¬ 
portunity  for  those  elements  to  accumulate  which  are  best  used  by  a 
succeeding  different  crop. 

How  Much  to  Use. — The  limit  of  profitable  application  of  nitrate 
of  soda  on  land  which  is  naturally  capable  of  producing  from  ten  to 
eighteen  tons  per  acre  is  probably  from  150  to  300  pounds  per  acre.  The 
larger  quantity  gives  more  profit  on  less  productive  land  than  on 
more  highly  productive  soil.  This  is  largely  due  to  the  fact  that 
there  seems  to  be  a  certain  limit  to  the  productiveness  of  a  soil,  due 
more  or  less  to  its  present  physical  state  of  condition,  no  matter  how 
-much  available  plant  food  is  present. 

In  one  case  580  pounds  per  acre  applied  to  land  which  produced 
11.5  tons  without  fertilization,  gave  a  small  profit,  but  not  nearly  as 
much  in  proportion  as  was  derived  from  smaller  amounts  applied  on 
the  same  land.  In  another  case  300  pounds  applied  to  a  soil  which 
produced  twenty-eight  tons  per  acre  without  fertilization  increased 
the  yield,  while  100  pounds  applied  to  the  same  soil,  was  without 
effect. 

Larger  quantities  can  sometime  be  applied,  depending  on  the 
soil,  with  an  increase  in  yield  it  is  true,  but  the  margin  between  the 
returns  from  the  increased  yield  and  the  cost  of  the  fertilizer,  will  not 
be  as  great  as  when  smaller  quantities  are  used  on  the  same  soil.  A 
point  will  be  reached  where  cost  of  the  fertilizer  applied  will  equal 
the  increase  in  yield.  And  in  the  case  of  nitrate  of  soda  an  amount 
much  beyond  that  point,  will  decrease  the  yield  even  below  the  normal 
productiveness  of  the  soil. 

WHEN  AND  HOW  USED 

Details  of  Application. — Cost. — No  matter  in  what  manner  the 
nitrate  is  applied  it  must  be  prepared  by  breaking  up  the  lumps  and 
coarse  particles  and  passed  through  a  one-fourth  or  one-third  inch 
sieve  or  screen.  It  can  then  be  broadcasted  before  the  last  harrowing 
before  seeding,  which  is  probably  the  best  method,  or  sown  with  the 
combined  seeder  and  fertilizer  drill  with  the  seed.  The  broadcasting 
can  be  clone  with  an  endgate  seeder  or  fertilizer  sower,  or  with  drills 
made  for  the  purpose.  When  sowing  the  nitrate  at  the  same  time  as 
the  seed  by  the  use  of  a  fertilizer  attachment  to  an  ordinary  beet  seed 
drill,  the  writer  has  found  that  unless  the  material  is  kept  agitated  it 
is  likely  to  “bridge”  similar  to  beet  seed,  and  stop  feeding. 

As  to  the  cost  of  application  it  has  been  found  that  by  the  use  of 
an  endgate  sower,  two  men  with  a  team  and  wagon  are  able  to  cover 
from  forty  to  fifty  acres  per  day  at  an  expense  of  $6.00  per  day,  or  at 
forty  acres  per  day,  fifteen  cents  per  acre.  The  screening  of  the 
nitrate  and  resacking  should  not  exceed  five  cents  per  hundred. 


FERTILIZER  EXPERIMENTS  WITH  SUGAR  BEETS.  23 

With  a  fertilizer  drill  distributor  with  one  man  and  a  team,  half  that 
number  of  acres  could  probably  be  covered.  When  drilled  with  the 

seed  the  only  duty  would  be  to  keep  the  hoppers  or  cans  full  and  pre¬ 
vent  ‘bridging.'  1 


SUMMARY  AND  CONCLUSIONS 


(1)  Our  Colorado  soils  generally  contain  ample  supplies  of  pot¬ 
ash  and  phosphoric  acid,  and  an  excess  of  lime. 

(2)  The  native  soil  is  generally  somewhat  deficient  in  nitroo-en 
ait  humus,  both  are  supplied  by  growing  leguminous  plants  like  al- 
talia,  peas,  vetches,  or  beans,  or  from  sheep  and  stable  manures. 
JNitiogen,  but  not  humus,  can  be  supplied  by  commercial  fertilizers. 

(3)  Nitrogen  in  the  form  of  nitrate  of  soda  is  the  only  element 

which  has  had  any  decided  effect  in  increasing  the  yield  of  suvar 
beets  over  the  cost  of  application.  J  gar 

(4)  Potash  and  phosphoric  acid,  from  sulphate  of  potash 
raw  bone  meal,  Basic  slag,  dissolved  or  acid  bone,  and  phosfate  rock' 
used  alone  or  together,  have  very  little  or  no  effect  upon  the  yield. 

(5)  There  are  strong  indications  that  potash  and  phosphoric 
acid  from  fertilizers,  largely,  if  not  entirely,  neutralize  the  effect  of 

nitrate  of  soda  upon  the  yield  of  sugar  beets,  although  the  quality  of 
the  beet  is  good.  #  1  J 

(6)  No  difference  in  results  were  obtained  between  applying  the 
nitrate  of  soda  at  the  time  of  planting,  or  in  part  at  the  time  of 
planting,  and  m  two  applications  during  the  growing  season. 

(7)  The  net  profit  from  reasonable  quantities  of  manure  if 
cost  of  manure  and  Hs  application  is  considerable,  is  mainly  obtained 
in  the  after  effects  m  the  succeeding  year,  while  there  appears  to  be 
no  residual  effect  the  third  year  after  application. 

(8)  An  excess  of  nitrogen  from  manures  or  fertilizers  over 

what  the  p  ant  needs  lowers  the  yield  and  the  quality  of  the  sugar 
beet  some  though  not  much.  ~ 


(9)  Reasonable  quantities  of  manure  were  fully  as  effective  as 
large  or  excessive  quantities. 

(10)  Refuse  lime  cake  from  the  sugar  factories  as  a  fertilizer  on 
sugar  beets  was  of  no  benefit. 

11()  Soluble  fertilizers  applied  to  the  seed  favored  strong  o-er_ 
mination.  & 


•  !  !  Very  hlgh  suSar  content  and  puritv  seem  to  go  with  low 

yields,  although  there  are  exceptions.  . 

(13)  bertilizers  will  not  take  the  place  of  good  preparation  or 
cultivation  of  the  soil,  or  good  care  of  the  crop.  The  soil  must  be  in 
good  physical  condition  to  make  the  best  use  of  fertilizers  applied 
. ,  (,14)  The  tops  were  about  forty-four  per  cent  of  the  weight  of 

the  clean  beets.  A  fifteen  ton  crop  of  sugar  beets  will  produce  6.6 

tons  fresh,  green  tops.  It  is  estimated  that  this  will  air-dry  to  one- 
eighth  the  original  weight  or  0.8  of  a  ton. 


Bulletin  116 


June,  1906 


The  Agricultural  Experiment  Station 

OF  THE 

# 

Colorado  Agricultural  College 


THE  COTTONY  MAPLE  SCALE 


By 


S.  A.  JOHNSON 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
Fort  Collins,  Colorado 
1906 


THE  AGRICULTURAL  EXPERIMENT  STATION 

FORT  COLLINS,  COLORADO 


THE  STATE  BOARD  OF  AGRICULTURE  term 


EXPIRES 

Hon.  P.  F.  SHARP,  President ,  -------  Denver,  -  1907 

Hon.  HARLAN  THOMAS,  -  ------  Denver,  -  -  1907 

Hon.  JAMES  L.  CITATFIELD,  ------  Gypsum,  -  1909 

Hon.  B.  U.  DYE,  -  -  -  -  -  -  -  Rockyford,  -  1909 

Hon.  B.  F.  ROCKAFELLOW,  ------  Canon  City  -  1911 

Hotf.  EUGENE  H.  GRUBB  ------  -  Carbondale,  -  1911 

Hon  A.  A.  EDWARDS.  -  --  --  --  -  Fort  Collins,  -  1913 

Hon.  R.  W.  CORWJN,  -------  _  pueblo  -  -  1913 

Governor  JESSE  F.  McDONALD,  \  ^  ...  . 

President  BARTON  O.  AYLESWORTK,  r'X"°  1C1°- 

A.  M.  HAWLEY,  Secretary  EDGAR  AVERY,  Treasurer 


EXECUTIVE  COMMITTEE  IN  CHARGE 

j  , 

P.  F.  SHARP,  Chairman 

B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS. 


STATION  STAFF 

L.  G.  CARPENTER,  M.  S.,  Director ,  -----  Irrigation  Engineer 


C.  P.  GILLETTE,  M.  S.,  -  -----  -  Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D.,  -  -  -  -  ____  Chemist 

W.  PADDOCK,  M.  S.,  -  -  -  Horticulturist 

W.  L.  CARLYLE,  M.  S.,  -  --  --  --  --  -  Agriculturist 

G.  H.  GLOVER,  M.  S.,  D.  V.  M.,  -  _______  Veterinarian 

W.  H.  OLIN,  M.  S.,  -  Agronomist 


R.  E.  TRIMBLE,  B.  S.,  _____  Assisj  pant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S.,  -------  --  Assistant  Chemist 

EARL  DOUGLASS,  M.  S ,  -  -  -  -  -  -  -  -  Assistant  Chemist 

S.  ARTHUR  JOHNSON,  M.  S.,  -  -  -  -  -  -  Assistant  Entomologist 

B.  O.  LONGYEAR,  B.  S.,  -  -  -  -  -  -  Assistant  Horticulturist 

J.  A.  McLEAN,  A.  B.,  B.  S.  A  ,  -  -  -  -  -  -  -  Animal  Husbandman 

E.  B.  HOUSE,  M.  S.,  ------  Assistant  Irrigation  Engineer 

F.  KNORR,  _-_  ______  _  Assistant  Agronomist 

P.  K.  BLINN,  B.  S.,  -  -  -  -  Field  Agent,  Arkansas  Valley,  Rockyford 

E.  R.  BENNETT,  B.  S.,  -  -  -  -  -  Potato  Investigations 

Western  Slope  Fruit  Investigations,  Grand  Junction: 

O.  B.  WHIPPLE,  B.  S.,  -  -----  _  _  Field  Horticulturist 

E  P.  TAYLOR,  B.  S.,  -  -  -  -  -  -  -  -  Field  Entomologist 


OFFICERS 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S.,  -  -  -  -  -  -  -  -  -  -  -  Director 

A.  M.  HAWLEY,  -  --  --  --  --  --  -  Secretary 

MARGARET  MURRAY,  -  -  -  -------  Clerk 


I 


The  Cottony  Maple  Scale 

Pulvinaria  innumerabil is  Rathvon. 

BY  S.  ARTHUR  JOHNSON. 


The  past  few  years  have  witnessed  a  recurrence  of  the  cottony 
maple  scale  in  injurious  numbers  in  several  parts  of  the  United  States. 
The  present  outbreak  has  brought  about  a  greater  activity  in  the  use 
of  remedial  measures  than  ever  before,  and  though  the  control  of  the 
insect  has  not  yet  been  .accomplished,  sufficient  has  been  learned  to 
point  the  way.  It  is  the  purpose  of  this  bulletin  to  gather  the  im¬ 
portant  points  of  economic  literature  and  the  series  of  experiments  and 
observations  made  at  this  station  so  that  what  is  now  widely  scattered 
may  be  immediately  available  to  those  who  need  the  information. 

The  most  bitter  complaints  of  injury  at  all  times  appear  to  have 
come  from  places  where  the  maple  tree  is  cultivated  for  shade.  The 
reasons  for  this  are  not  positively  known,  but  we  are  tempted  to 
speculate  that  itf  is  due  to  the  artificial  conditions  under  which  the 
trees  are  placed.  Under  forest  conditions  the  insect  appears  to  be  kept 
in  check  by  its  natural  enemies,  which  doubtless',  find  shelter  and  pro¬ 
tection  in  their  native  haunts  which  are  denied  them  among  trees 
planted  on  private  grounds  and  in  parks. 

Thus  far  the  remedies  and  their  application  are  rather  expensive, 
but  are  amply  justified  when  we  consider  that  a  beautiful  tree  is  the 
work  of  years  and  cannot  readily  be  replaced  except  by  a  repetition  of 
the  long  years  of  waiting. 

SYNONOMY 

Riley  in  the  report  of  the  Commissioner  of  Agriculture  for  1884, 
has  summarized  the  synonomy  of  the  species  to  that  date  and  to  that 
article  I  am  chiefly  indebted  for  this  paragraph.  The  insect  was  first 
described  as  Coccus  innumerabilis  by  Dr.  S.  S.  Rathvon  of  Lancaster, 
Pa.,  in  the  “Pennsylvania  Farm  Journal”  (Vol.  IV,  pp. 256-258,  Aug., 
1854.)  Five  years  later,  Dr.  Asa  Fitch  redescribed  it  in  the  “Trans¬ 
actions  of  the  New  York  State  Agricultural  Society”  (Vol.  XIX,  pp. 
7/5-776)  under  the  name  of  Lecanium  cicericorticis .  A  third  descrip¬ 
tion  was  made  by  Walsh  aed  Riley  in  the  American  Entomologist 
(Vol.  I,  p.  14,  1869)  as  Lecanium  acericola ,  the  previous  descriptions, 
having  been  overlooked.  A  closely  allied  form  on  the  osage  orange, 
received  from  these  last  writers  the  name  L .  maclurce .  After  the  pub¬ 
lication  of  the  names  given  by  Riley  and  Walsh,  Dr.  Rathvon  called 
the  attention  of  these  entomologists  to  his  description  and  subsequent 


<% 


4 


BULLETIN  116. 


correspondence  showed  that  the  species  were  identical.  Glover  in 
1877  revived  Fitch’s  name  of  Lecanium  acericorticis  which  had  been 
overlooked  up  to  that  time. 

While  this  portion  of  the  problem  of  synonomy  was  being  thrashed 
out,  Mr.  J.  Duncan  Putnam  was  making  a  careful  study  of  the  life  his¬ 
tory.  Four  articles  came  from  his  pen.  The  first  three  were  printed 
under  Walsh  and  Riley’s  name  of  Lecanium  acericola .  (*).  The 

fourth  article  is  a  very  thorough  study  of  the  life  history  covering 
some  fifty  pages  of  text  and  accompanied  by  two  plates.  (**).  In 
it  the  author,  at  the  suggestion  of  Prof.  Riley,  restored  the  original 
name  of  innumerabilis  and  transferred  the  species  to  the  genus  Pul- 
v  in  aria. 

While  this  discussion  appeared  to  clear  the  field  to  the  point  given 
it  was  far  from  doing  so.  It  appears  that  Walsh  and  Riley,  Putnam 
and  other  writers  had  collectively  confused  at  least  three  distinct 
species.  This  state  of  affairs  was  discovered  by  Dr.  Howard  and  unraveled 
by  him  in  1900.  (***) .  In  their  original  article  W alsh  and  Riley  had  really 
included  two  species  in  both  the  cut  and  description;  one  in  which  the 
female  reached  the  adult  stage  on  the  twigs  and  corresponds  to  P. 
innumerabilis  Rathv. ,  and  a  second  which  matures  on  the  leaves  and 
receives  the  name  P.  acericola  W.  &  R.  A  third  form,  P.  maclura 
occurring  on  osage  orange  had  been  considered  synonymous  with  P • 
innumerabilis  by  some  writers.  Prof.  Cockerell  has  since  examined 
this  and  considers  it  entirely  distinct.  To  the  western  form  the  latter 
writer  has  given  the  varietal  name  of  occidentalism  If  this  should  prove 
to  be  a  distinct  species  it  will  raise  again  the  question  of  its  introduction. 
Some  of  the  scales  found  on  food  plants  widely  separated  from  maple 
may  yet  be  found  to  be  distinct  from  P.  innumerabilis. 

§ 

DISTRIBUTION 

This  insect  is  a  native  of  the  United  States  and  our  literature 
dates  from  its  discovery  by  Dr.  S.  S.  Rathvon  in  Pennsylvania.  It 
has,  however,  long  been  widely  distributed  over  the  country.  (See 
Fig.  1.)  Mr.  Sanders  calls  attention  to  the  fact  that  the  insect  is 
preeminently  an  inhabitant  of  the  upper  austral  zone,  though  some¬ 
times  it  penetrates  the  transitional.  In  other  words  it  is  found  in  the 
middle  zone  of  states  extending  from  the  Atlantic  coast  to  the  Rocky 
mountains.  Outside  of  this  range  it  is  found  northward  in  New  York, 
Michigan  and  Wisconsin.  To  the  south,  branches  appear  to  follow 
the  highlands  into  Tennessee,  Georgia  and  North  Carolina  and  at  the 
western  extremity  into  Texas.  Mr.  Gossard  found  it  on  pecans  in 
Florida,  where  in  some  cases,  it  was  doing  considerable  injury.  In  the 
western  states  the  pest  is  reported  from  Washington,  Oregon,  Idaho 
and  California  (both  northern  and  southern)  where  it  is  believed  to  be 
an  introduced  insect. 


*(Prof.  Davenport  Academy  of  Nat.  Sci.,Vol.  I.,  p.  37,  1876;  Davenport  Daily 
Gazette,  June  5, 1877;  Trans.  Iowa  Horticultural  Soc.,  1877,  pp.  317-324.) 

** (Proceedings  Davenport  Acad.  Nat.  Sci.,  Vol.  II,  Part  V.,  pp.  297-347, 1879.) 
***(U.  S.  Dept.  Agr.  Division  of  Entomology,  Bui.  22,  n.  s.) 


THE  COTTONY  MAPLE  SCALE 


5 


FOOD  PLANTS 

The  host  plants  of  this  species  are  very  widely  distributed  among 
trees,  shrubs  and  vines.  Sanders  states  that  the  list  comprises  forty- 
seven  varieties  and  species.  But  few  of  these  are  of  economic  im¬ 
portance  for  they  are  seldom  badly  infested.  The  greatest  sufferer  is 
the  food  plant  from  which  the  insect  receives  its  name,  the  soft  or 
silver  leaved  maple  (  Acer  sacca?dnum  ).  Next  in  importance  are  the 
box  elder  (  Acer  negundo  ),  black  locust  and  elm.  It  has  also  been  found 
in  large  numbers  on  pawpaw  in  Illinois.  Mr.  H.  E.  Weed  gives  as  less 
seriously  affected,  linden  {Telia) ,  Virginia  creeper  (Ampelopsis  quin- 
quifolia ),  bittersweet  (  Celaslrus  scandens),  sumac  ( Rhus ),  grape 
(  V it  is ) ,  and  willow.  Together  with  some  of  the  above,  other  writers 
have  mentioned  poplar,  beech,  hawthorne,  sycamore,  hackberry,  mul¬ 
berry,  poison  ivy,  rose,  basswood,  and  ash.  In  Georgia  the  oak  is  re¬ 
ported  as  being  seriously  affected.  Singularly,  sugar  and  Norway 
maples  seem  to  be  but  little  injured  even  where  they  are  surrounded  by 
badly  infested  host  plants. 

Among  fruit  trees,  the  pear  is  the  greatest  sufferer.  Apple,  plum, 
peach,  currant  and  gooseberry  are  also  sometimes  attacked. 

Some  plants  serve  as  hosts  during  the  summer,  but  do  not  appear 
to  winter  over  the  insect.  A  list  given  by  Mr.  Weed  includes  Spircea 
Van  Houtenii,  S.  arguta,  S.  prunifolia,  Philadelphus  ^randifloris,  P.  coro- 
narius,  Cornus  mascn/a,  C.  sibej-ica,  C.  stolonifera,  Ribes  aureum,  R.  sangui- 
nium ,  Hydrangea ,  Rudbeckia ,  Syringa  and  Vibernum. 

The  western  form,  which  is  known  as  occidentalism  appeal's  to  be 
fastidious  in  its  tastes  or  has  imbibed  the  western  spirit  of  a  desire 


6 


BULLETIN  116. 


/ 


for  new  things,  for  Mr.  Piper  states  that  it  is  n6t  found  abundantly  on 
the  native  maples,  but  infests  currant,  gooseberry,  plum,  pear,  haw- 
thorne,  mountain  ash,  Lombardy  poplar,  weeping  willow,  currants 
{Ribes  sanguinum) ,  and  species  of  willow  (Salix  flavescens  and  S.  lanadrd). 

A  careful  study  of  the  forms  on  all  of  these  food  plants  has  not 
been  made  and  it  will  be  wise  to  make  a  mental  reservation  as  to  the 
identity  of  the  species  in  some  cases  until  further  evidence  is  forth¬ 
coming. 

The  economic  history  of  the  insect  shows  that  its  destructive 
abundance  in  certain  localities  is  periodic.  The  data  at  hand  fail  to 
show  that  this  periodicity  is  amenable  to  any  law,  though  there  have 
been  two  periods  of  general  abundance  over  its  range.  The  statement 
has  been  widely  circulated  that  the  scale  is  seldom  injuriously  abundant 
two  years  in  succession,  but  this  has  been  proved  to  be  untrue  within 
the  past  few  years  in  widely  separated  localities.  In  the  early  eighties 
there  was  a  general  visitation  of  the  pest  and  Dr.  Forbes  'made  a  num¬ 
ber  of  preliminary  experiments  looking  toward  control.  On  this  occa¬ 
sion  the  insects  appeared  in  great  abundance  in  1880  and  1884,  subsid¬ 
ing  to  insignificant  numbers  during  the  intervening  years.  A  second 
scourge  occurred  during  the  past  five  years  and  is  reported  by  Mr. 
Chittenden  as  being  more  generally  abundant  over  its  range  than  at 
any  previous  year.  The  city  parks  of  Denver  and  Chicago  seem  to  be 
the  storm  centers.  In  the  latter  place  the  lower  limbs  of  the  silver 
maples  have  been  killed  in  great  numbers,  leaving  the  trees  unshapely 
in  appearance.  Many  hundreds  of  trees  have  been  killed  outright. 
In  Denver  the  destruction  has  been,  perhaps,  less  severe,  but  weeks 
were  spent  cleaning  dead  limbs  out  of  the  parks  and  many  trees  along 
the  more  crowded  streets  have  been  injured  to  such  an  extent  that  they 
are  practically  worthless. 

LIFE  HISTORY 

When  the  sap  begins  to  flow  in  the  food  plant  the  young  hiber¬ 
nating  females  begin  to  suck  up  the  fluid  rapidly  and  to  grow.  In  a 
few  weeks  they  have  increased  their  size  about  four  times.  At  this 
stage  the  scales,  which  before  may  have  been  unnoticed  because  of 
their  flat  position  on  the  bark  and  similarity  to  it  in  color,  become 
suddenly  conspicuous  on  account  of  the  white  cottony  mass  of  wax 
which  is  thrust  out  from  under  the  posterior  end.  This  mater¬ 
ial  is,  composed  of  wax  threads  spun  from  the  ventral  glands  of 
the  animal,  especially  those  located  on  the  margins,  and  serves 
as  an  ovisac.  (See  Fig.  2.)  The  quantity  is  enormous  for  the 
size  of  the  insect.  The  extrusion  of  it  gradually  raises  her  body 
from  its  flat  position  on  the  twig  until  it  stands  out  at  an  angle  of  some 
sixty  degrees  or  even  vertically.  During  this  period  the  egg  laying 
proceeds.  This  takes  place  at  different  times  in  different  localities 
and  seasons,  varying  with  the  temperature  and  in  some  cases  with  the 
food  plants.  In  Florida  when  thi^  scale  appears  on  pecans,  Gossard 
states  that  the  ovisacs  become  conspicuous  during  April  and  May.  In 
most  other  places  they  appear  in  May  or  June. 


THE  COTTONY  MAPLE  SCALE 


7 


The  egg  laying  extends  over  almost  the  entire  period  of  cotton 
secretion,  but  is  most  active  during  June.  In  many  cases  it  doubtless 
begins  in  May  and  extends,  in  some  cases  at  least,  into  July. 


Fig.  2.  Females  of  the  cottony  maple  scale :  a,  ovisac  opened  to  show  eggs  ;  b,  females  with 
cottony  mass  partly  secreted ;  c,  slightly  enlarged  female  ;  d,  parasitized  winter  form  ; 
d’  the  same  slightly  enlarged  ;  e,  hibernating  winter  form.  All  except  c  and  d’  natur, 
al  size.  (Drawn  by  Miss  M.  A.  Palmer). 

The  eggs  aie  tiny  oval  spheroids,  pale  cream  in  color.  The  num¬ 
ber  as  given  by  the  older  entomologists  is  from  one  to  two  thousand. 
These  figuies  are  probably  somewhat  too  large  and  more  recent  writers 
have  reduced  the  estimate.  Cotton  mentions  from  three  hundred  to 
one  thousand  and  Sanders  says  that  the  number  may  reach  fifteen 
hundred. 

The  egg  hatching  likewise  consumes  considerable  time.  To 
quote  from  Dr.  Howard  on  observations  made  in  Washington,  D.  C.; 

“The  young  lice  hatch  early  in  summer,  usually  in  June,  but  occassionally  at 
least  as  early  as  May  22.  The  hatching  period  usually  extends  on  into  early  July 
but  may  last  until  August.” 

Seasonal  influences  appear  to  bear  considerable  weight.  Mr.  H. 
E.  Weed  makes  the  following  note  of  conditions  in  Chicago  in  1904: 

“During  the  past  summer  the  eggs  were  slow  in  hatching,  as  the  season  was  very 
backward.  Up  to  June  25,  practically  no  eggs  were  hatched.  Two  ciuite  warm  days 
occ  urred  about  July  10,  and  this  served  to  bring  them  out.” 

In  the  visitation  of  1884,  Dr.  4  orbes  states  that  the  young  were 
abundant  by  the  middle  of  June,  but  in  some  localities  25  per  cent  of 
the  eggs  were  not  hatched  on  July  19.  Colorado  observations  give  the 
following:  “June  22,  1901.  Scales  from  Delta  and  Montrose  were 
full  of  eggs,  but  no  lice  hatching  yet.”  “July  2,  1902.  All  hatched 
and  beginning  to  scatter  from  twigs  of  soft  maple  from  Colorado 
Springs.”  “Denver,  June  10,  1904.  The  scales  are  just  be  ginning  to 
raise  and  expose  the  cottony  secretion  of  the  louse.  I  find  on  examin¬ 
ing  these  scales  that  a  few  eggs  have  already  been  deposited.”  The 
foregoing  notes  were  made  by  Prof.  Gillette. 

On  July  15,  1905,  I  visited  the  parks  of  Denver  and  found  that 
most  of  the  eggs  had  already  hatched.  In  fact,  unhatched  clusters 
were  very  difficult  to  find.  There  appears  to  be  an  unexplained 
phenomena  in  that  the  eggs  laid  on  some  trees  hatch  at  times  differing 


8 


BULLETIN  116. 


from  their  neighbors.  Young  lice  have  been  known  to  appear  upon 
box  elder  before  maple. 

The  newly  hatched  young  remain  a  day  or  two  in  the  ovisac  and 
then  migrate  to  the  leaves  where  they  attach  themselves  to  the  ribs  or, 
rarely,  to  the  young  twigs.  In  doing  this  they  prefer  the  under  sides 
and  larvse  so  situated  appear  to  grow  more  rapidly  than  those  other¬ 
wise  located.  In  times  of  serious  infestation  these  locations  soon  be¬ 
come  preempted  and  the  young  swarm  over  every  green  thing  within 
a  short  radius  of  their  home.  It  is  in  these  cases  that  the  summer  food 
plants  serve  as  hosts.  On  some  of  these  they  seem  to  prosper  fairly 
well.  Dr.  Forbes  found  that  the  males  reached  maturity  on  straw¬ 
berry  plants,  and,  as  an  isolated  maple  tree  which  had  been  thoroughly 
treated  during  the  summer  was  reinfested  in  the  fall,  concluded  that  the 
females  had  found  their  way  back  from  temporary  food  plants. 

Shortly  after  the  young  begin  to  feed  a  delicate  waxy  scale  forms 
over  the  back. 

The  first  molt  occurs  in  from  three  to  four  weeks  from  the  hatching 
of  the  egg.  It  was  observed  in  Washington  as  early  as  June  10.  At 
this  time  the  insects  are  about  twice  their  size  at  hatching. 

After  this  molt  the  differences  in  the  sexes  is  observable.  “The 
males  grow  more  slender  and  soon  cease  to  increase  in  size,  covering 
themselves  with  a  thin  coating  of  wax.’’  At  this  stage,  according  to 
Howard,  the  second  molt  takes  place  beneath  the  scale  and  a  propupal 
stage  occurs.  (See  Fig.  3.) 


Fig.  3.  PULVINARIA  IMMUMERABILIS  :  a,  adult  male  ;  b,  antennae  of  same  ;  c,  leg  of 
same;  d,  second  stage  of  pupa ;  e,  cast  skin  of  same ;  f.  true  pupa  ;  g,  cast  skin  of  same 
All  greatly  enlarged,  b  and  c  still  more  enlarged.  (Howard  Bui.  22,  Div.  of  Ent<  m., 
U.  S.  Dept.  Agr.) 

“In  a  few  days  the  pupa  casts  its  skin  and  assumes  the  true  pupa  form,  which, 
during  its  earl  ier  stages  is  a  pale  green  color,  becoming  dark  flesh  color  at  a  later  date.” 
“The  antennae  which  up  to  this  time  were  seven-jointed,  had  now  become  eight- 
jointed.  There  seemed  to  be  two  propupa  stages.  After  casting  the  second  skin, 


THE  COTTONY  MAPLE  SCALE 


9 


the  male  larvae  looses  its  rostrum  and  its  anal  cleft,  although  the  wing  pads  have  not 
yet  developed;  the  antennae  are  stout  and  laid  backward  without  perceptible  joints, 
and  that  end  of  the  body  is  furnished  with  two  long  conical  tuberculae.  After  the 
third  skin  is  cast,  an  apparent  propupal  stage  is  found  which  bears  wing  pads  reaching 
to  the  abdomen;  the  claw  of  the  tibia  is  lost,  and  between  the  posterior  tubercles  has 
appeared  a  stout,  rudimentary  style.” — Howard.  “A  long  pair  of  wax  filaments  is 
secreted  from  the  anal  extremity  and  these  continue  to  grow  during  the  life  of  the 
insect.  It  is  the  protrusion  of  these  filaments  from  beneath  the  waxy  scale  which 
indicates  the  approaching  exclusion  of  the  male.” — Riley. 

The  changes  in  the  female  scales  are  less  conspicuous  but  never¬ 
theless  characteristic.  After  the  first  molt  they  broaden  posteriorly 
and  have  a  slight  dorsal  carina.  When  the  males  appear,  they  have 
undergone  a  second  molt  and  changed  from  pale  yellow  to  light  green 
and  are  marked  with  a  brown  dorsal  stripe  the  whole  length  of  the  body. 

The  males  appear  during  the  latter  part  of  August  or  first  of  Sep¬ 
tember,  copulate  with  the  females  in  a  few  days  and  die. 

The  summer  injuries  are  most  conspicuous  on  the  leaves.  Dr. 
Forbes  states  that  in  1884  many  trees  at  Bloomington,  Ill.,  had  lost  a 
considerable  portion  of  their  leaves  by  August  16,  and  the  others  were 
blackened  and  dwarfed,  giving  the  branches  a  bare  and  unthrifty  look. 

In  early  October  the  gravid  females  desert  the  leaves  and  find 
places  for  hibernation  on  the  branches  and  twigs.  Immense  numbers 
drop  to  the  ground  with  the  falling  leaves  which  results  in  a  great  loss 
of  life  from  the  inability  of  many  to  find  their  way  back.  The  position 
sought  is  the  under  sides  of  the  twigs  and  smail  branches,  the  lower 
branches  of  the  tree  being  usually  most  densely  populated.  Many 
locate  around  the  crotches  and  on  the  upper  sides  of  the  twigs.  The 
scales  are  still  quite  flat  and  about  one  fourth  grown,  varying  from  one 
and  one  half  to  two  and  one  half  millimeters  in  length.  The  posi¬ 
tion  assumed  on  the  twig  is  more  often  lengthwise  than  crosswise  and 
the  number  may  be  as  great  as  the  bark  will  accomodate.  (See  Fig. 
2  e.)  The  color  changes  at  this  time  from  a  light  green  to  light  brown. 
It  is  very  doubtful  if  any  nourishment  is  taken  from  this  time  till  the 
spring  activities  begin.  The  mortality,  outside  of  parasitism,  during 
this  period  is  considerable  and  varies  greatly  with  different  twigs  and 
trees.  The  check  twigs  counted  from  trees  in  Denver  showed  this  to 
vary  from  twenty-five  to  sixty-two  per  cent. 

SPREAD  OF  THE  INSECT 

But  few  instances  of  the  transportation  of  the  insect  have  been 
observed,  and  these  are  of  such  a  nature  as  to  account  for  but  a  small 
portion  of  the  infestation.  The  most  fruitful  source  in  the  past  has 
doubtless  been  through  the  transplanting  of  trees,  for  this  is  done 
when  the  insect  is  firmly  attached  in  the  hibernating  stage.  Over  short 
distances  they  may  be  transported  on  the  feet  of  birds  or  clinging  to  the 
parts  of  insects.  The  eggs  hatch  during  summer  when  there  is  little 
migration  among  birds  so  that  great  distances  are  probably  not  made  in 
this  way.  It  is  not  probable  that  many  migrations  of  this  kind  arc 
made  in  the  fall  when  the  insect  is  moving  from  the  leaves  to  the  twigs, 
since  the  insects  at  this  time  are  probably  too  large  to  be  readily  carried 
by  these  means.  Either  the  newly  hatched  young  or  gravid  females 
may  be  transferred  from  tree  to  tree  by  the  interlocking  of  limbs  or  by 


10 


BULLETIN  110. 


first  falling  to  the  ground.  Prof.  Garman  found  a  goldfinch’s  nest 
covered  on  the  outside  with  nests  of  Pulv inaria.  Mr.  Hubbard  believed 
that  spiders  were  the  chief  means  of  transportation. 

ENEMIES 

As  might  be  expected,  the  cottony  maple  scale,  being  a  native 
insect,  is  preyed  upon  by  a  wide  range  of  enemies  which  includes  both 
those  which  prey  upon  insects  in  general,  and  the  groups  which  confine 
themselves  to  a  smaller  range  of  hosts. 

The  only  instance  of  a  vertebrate  being  among  the  group  was 
observed  by  Dr.  Howard,  when  he  saw  an  English  sparrow  eating  the 
waxy  masses  in  Washington.  That  these  birds  do  not  offer  much  hope 
of  relief  is  evident  when  we  remember  that  the  most  serious  outbreaks 
of  the  pest  have  occurred  in  those  places  where  this  sparrow  is  most 
abundant. 

The  Arachnida  have  come  to  the  rescue  but  once  and  that  was 
when  the  harvest  mites  were  found  by  Miss  Murtfeldt  feeding  upon  the 
eggs  in  Missouri. 

The  larvae  of  a  species  of  lace  winged  flies  ( Chrysopa )  and  two 
species  of  assassin  bugs  ( Reduviidc ? )  were  found  by  Mr.  Putnam  to 
feed  upon  the  scales.  In  Denver,  the  nymphs  of  what  Mr.  Ashmead 
has  determined  as  Corizus  hyalinus  were  found  working  among  the 
egg  masses. 

Probably  more  important  than  any  of  the  foregoing  are  the  ever 
faithful  ladybirds.  Chilochorus  bivulnerus  during  all  stages  of  its 
life,  but  especially  while  young,  feeds  upon  this  insect.  Several  species 
of  Hyperaspis  notably  H.  signata,  //.  bigeminata  and  //.  binotata  do  good 
service,  while  to  these  must  be  added  Rhizobius  ventralis. 

The  larvae  of  a  species  of 'small  moth,  described  by  Prof.  Com¬ 
stock  (*)  as  Dakruma  (. Lcstilia )  coccidivora  did  very  effective  service  in 
Washington,  D.  C.  According  to  Dr.  Howard: 

“This  caterpillar  flourished  upon  the  twigs  upon  which  the  scales  were  close¬ 
ly  massed  together,  and  ate  its  way  through  the  mass  from  one  scale  to  another, 
spinning  a  close  rather  dense  web  as  it  progressed.  Each  caterpillar  in  this  way 
destroyed  very  many  scale  insects.  The  writer  has  always  thought  that  it  was  due 
to  this  insect  alone  that  the  cottony  cushion  scale  ‘  almost  disappeared  from  the 
Washington  shade  trees  in  the  close  of  1879,  and  was  never  seen  here  again  until, 
in  the  summer  of  1898,  nineteen  years  later,  it  became  once  more  rather  conspic¬ 
uous,  although  by  no  means  as  abundant  as  in  the  former  year.  The  Dakruma 
not  only  destroys  the  old  wornout  female,  but  devours  her  eggs  and  young  larvae 
with  avidity.  The  caterpillars  are  very  active,  moving  about  freely  within  their 
silken  passages.  They  were  to  be  found  full  grown  on  June  24,  spun  their  cocoons 
within  the  silken  tunnel,  and  remained  ten  days  in  the  pupal  state.  The  moths 
issued  from  July  17  to  August  13,  soon  thereafter  ovipositing  and  laying  their  eggs, 
which  hatched  in  six  days.  Whether  another  generation  of  moths  issues  the  same 
year  has  not  been  determined.” 

Prof.  Riley  states  that  in  Florida  this  larvae  attacks  “a  large 
Lecaniuvi  on  magnolia,  a  coccid  allied  to  Dactylopius  and  the  com¬ 
mon  “turtle  back  scale.” 

But  the  credit  for  the  most,  effective  work  of  eradication  of  the 
cottony  maple  scale  is  due  after  all  to  the  chalcid  parasites.  The 
general  insect  enemies  are  helpful  at  all  times,  and  in  some  cases  be¬ 
come  quite  important,  the  Daknnna  larvae  have  been  locally  beneficial, 


(*)  Report  Dept.  Agr.,  1879,  241-243. 


THE  COTTONY  MAPLE  SCALE 


11 


but  the  scale  is  never  able  to  withstand  the  onslaught  of  the  chalcid 
parasites.  The  most  important  of  these  is  Coccophagus  lecanii  Fitch 
This  minute  parasite  was  reared  by  Putnam  during  his  study  of  the 
insect  and  appeared  in  Washington,.  D.  C.,  in  such  numbers  in  1898  as 
to  interrupt  the  experiments  of  Dr.  Howard.  It  is  very  widely  dis¬ 
tributed  and  has  been  reared  from  other  scales  of  the  Lecanine  group. 
The  adult  is  a  minute,  black  four-winged  fly,  marked  with  a  crescent 
shaped  yellow  patch  in  the  middle  of  the  body  above.  Dr.  Howard 
states  that  less  than  one  per  cent  of  the  larvae  which  settled  upon  the 
leaves  under  his  observation  escaped  destruction  by  this  parasite. 
The  scales  were  stung  during  midsummer.  They  afterward  turned 
black  and  the  parasites  emerged  through  holes  out  of  their  backs. 
The  development  of  the  parasite  was  very  rapid,  not  occupying  more 
than  two  or  three  weeks..  Mr.  Putnam  believed  that  there  were  two 
generations,  but  Dr.  Howard  thinks  that  there  may  be  many  more. 
Closely  allied  to  this  species  is  C.  flavoscutellum  which  does  for  the 
southern  range  of  the  scale  the  work  accomplished  in  the  north  by 
C.  lecanis.  Its  range,  however,  is  not  confined  to  the  south  for  it  has 
been  reared  by  the  writer  from  scales  taken  in  Denver. 

The  other  chalcid  parasites  appear  to  be  of  less  importance. 
Corny s  fusca  Howard  is  a  common  parasite  on  Lecanine  scales  and 
widely  distributed.  Aphycus  Pulvinaria;  Howard  was  reared  by  Mr. 
Putnam,  and  Atropates  collUii  Howard  was  bred  in  both  1889  and  1891 
by  Dr.  Howard  from  females  of  the  cottony  maple  scale  from  Brooklyn 
and  Roslyn,  N.  Y.  Eunotus  lividus  Ashmead  has  been  reared  in  March 
and  April  from  old  scales,  the  parasites  spinning  clusters  of  stout 
cocoons  under  the  bodies  of  the  old  scales.  Specimens  were  reared  by 
the  writer  from  egg  masses  taken  in  Denver  during  July.  (See  Fig. 
4.)  In  each  case,  however,  there  was  but  one  cocoon  under  each 
scale.  Specimens  of  C heiloneurus  albicornis  have  been  found  in  our 
breeding  cages. 


Fig. 


4.  EUNOTUS  LI VI OUS,  greatly  enlarged,  with  male  and  female  antenna  above¬ 
still  more  enlarged.  ( Howard  Bui.  22.  Div.  of  Entom.,  U.  S.  Dept.  Agr.) 

'  REMEDIES 

The  history  of  the  remedies  is  very  brief  owing  to  the  fact  that 


12 


BULLETIN  116. 


the  insect  has  not  often  been  a  serious  pest  in  any  one  locality  long 
enough  for  the  problem  to  be  worked  out. 

Summer  Treatment. — In  1884  Dr.  Forbes  made  a  number  of  pre¬ 
liminary  laboratory  experiments  on  the  effect  of  insecticides  on  young 
lice.  A  leaf  dipped  in  per  cent  kerosene  emulsion  showed  that  the 
lice  were  killed.  A  branch  treated  in  the  same  way  showed  a  mortal¬ 
ity  of  three-fourths  in  twenty-four  hours.  A  branch  sprayed  with  the 
same  preparation  showed  one-half  dead  after  four  days.  A  branch 
dipped  in  five  per  cent  solution  killed  all.  Whale  oil  soap  appeared  to 
be  less  satisfactory  for  the  larvae  were  not  all  killed  with  a  solution 
weaker  than  one  pound  to  two  gallons,  and  these  strengths  all  did 
greater  or  less  injury  to  the  foliage. 

In  the  summer  of  1904,  Mr.  H.  E.  Weed  did  considerable  spraying 
in  the  parks  of  Chicago.  The  work  began  in  the  middle  of  July  and 
extended  to  the  first  of  September.  Kerosene  emulsion  of  eight  or  ten 
per  cent  strength  was  used  at  first,  but  afterward  increased  until  fifteen 
per  cent  was  reached.  The  results  I  give  in  his  own  words: 

‘Practically  none  of  the  insects  were  killed  with  either  the  eight  or  ten  percent 
emulsions.  An  examination  at  Prof.  Forbes’  office  of  leaves  sprayed  with  12%  per¬ 
cent  some  days  after  showed  that  something  over  fifty  per  cent  were  killed  but  the 
death  of  some  of  these  was  doubtless  due  to  natural  causes.  The  fifteen  per  cent 
emulsion  killed  the  greater  portion  of  the  Pulvinaria ,  but  as  this  strength  took 
practically  all  of  the  leaves  off  the  boxelder,  all  from  the  lindens  and  fully  one-half 
from  the  maples,  the  remedy  was  at  least  equal  to  the  disease.” 

The  failure  of  these  later  treatments  compared  with  those  of  Dr. 
Forbes  is  doubtless  due  to  the  age  of  the  young  scales.  It  is  probable 
that  the  greater  portionof  the  young  larvae  were  protected  by  waxy  ex¬ 
cretions  of  considerable  thickness  by  the  middle  of  July.  From  ex¬ 
periments  which  are  described  below  I  am  convinced  that  the  newly 
hatched  larvae  are  very  easily  killed.  Kerosene  emulsion  as  low  as 
five  per  cent  and  Good’s  whale  oil  soap  as  weak  as  one  pound  to  four 
gallons  appeared  to  be  entirely  effective. 

From  the  foregoing  it  must  appear  that  a  summer  spray  for  the 
young  scales  alone  must  be  a  very  protracted  and  expensive  task.  It 
is  probable  that  a  weak  spray  will  not  be  effective  on  a  scale  more  than 
a  week  or  ten  days  old.  The  greater  portion  of  the  eggs  hatch  probably 
between  the  middle  of  June  and  the  first  of  August.  Thiswould  neces¬ 
sitate  from  four  to  six  very  thorough  treatments  to  greatly  reduce  the 
numbers,  even  granting  that  all  of  the  lice  may  be  reached  by  each 
spray,  a  condition  which  anyone  who  has  had  very  much  practical  ex¬ 
perience  would  hesitate  to  admit. 

In  the  summer  of  1904,  the  writer  made  a  number  of  preliminary 
experiments  for  the  purpose  of  pointing  the  way  to  a  summer  treat¬ 
ment.  Since  these  have  not  been  published  before  they  are  given  in 
full.  The  first  eleven  were  treated  on  July  3,  and  the  others  on  July  5. 
The  examinations  were  all  made  on  July  14,  and  eggs  which  appeared 
to  be  alive  in  Nos.  4,  5,  10,  and  16  were  isolated  and  examined  July  26. 

TABULATED  STATEMENT  OF  TESTS  WITH  INSECTICIDES 

EXP.  CONDITIONS.  INSECTICIDE  RESULTS 

1  Large  scale  full  of  unhatched  Ker.  Emul.  50%  Everything  soaked 
eggs.  Some  larvae  kerosene  with  oil  and  dead, 

running  about. 


THE  COTTONY  MAPLE  SCALE 


13 


TABULATED  STATEMENT  OF  TESTS  WITH  INSECTICIDES  (CONTINUED) 


EXP. 

CONDITIONS 

INSECTICIDE 

RESULTS 

2 

Four  large  scales.  Eggs  and 
larvse. 

Ker  Emul.  33  1-3%  Everything  soaked 
kerosene  with  oil  and  dead 

3 

Several  large  females.  Eggs 
and  larvse. 

Do.  25% 

Everything  appears 
to  be  dead. 

4 

Mass  of  females. 

Eggs  and  larvae. 

Do.  20% 

Emulsion  penetrated 
well.  A  few  eggs  un 
der  one  scale  ap¬ 
peared  to  be  alive, 
but  failed  to  hatch 
by  VII,  26. 

5 

Isolated  females. 

Eggs  and  larvae. 

Do.  15% 

Larvse  and  most  eggs 
dead.  Two  scales 
had  fresh  eggs  un¬ 
der  them,  some  of 
which  had  hatched 
by  VII,  26. 

6 

Isolated  large  female 

Do.  10% 

Larvse  reached  are 
dead.  Emulsion 
did  not  penetrate. 
Abundance  of  eggs 
and  larvse  in  center 
of  masses. 

7 

Clustered  females. 

Well  protected  eggs  and 
larvae. 

Do.  5% 

Exposed  larvae  and 
eggs  under  smaller 
scales  all  dead. 

Large  masses  with 
many  young. 

8 

Scattered  females. 

Tak-a-nap,  1  lb 
to  1  gal.  water. 

Penetrated  and  k  illed 
well.  Two  1  i  ve  1  ice 
under  one  scale. 

9 

Large  masses. 

Do.,  1  lb  to  \}/2 
gal.  water 

Everyth  ing  appears  to 
be  dead. 

10 

Masses  of  females  and  eggs. 

Do.,  1  lb  to  2  gal 
water. 

Everything  dead  ex¬ 
cept  possibly  one 
large  mass.  Eggs 
did  not  hatch  by 
VII,  26. 

11 

Isolated  females. 

Do.  1  lb  to  3  gal. 
water. 

Penetrated  well. 
Everything  dead. 

13 

Isolated  scales. 

Not  large. 

Good’s  whale  oil 
soap,  1  lb  to  V/2 
gal.  water. 

Eggs  and  larvse  all 
killed. 

14 

Many  females,  larvae  and 
eggs. 

Do.l  lb.  to  2  gal 
water. 

Masses  penetrated  and 
everything  killed. 

15 

Do. 

Do.  1  lb.  to  3  gal 
water. 

Everything  exposed, 
dead.  A  few  live 
larvse  under  two 
scales. 

16 

Clustered  females. 

Do.  1  lb.  to  4  gal. 
water. 

•Eggs  and  larvse  k  illed 
where  reached. 

Penetration  poor. 
Eggs  from  center 
masses  hatched  by 
VII,  26. 


14 


BULLETIN  116. 


The  preparations  were  applied  in  the  laboratory  by  means  of  an 
atomizer.  An  examination  of  the  table  shows  that  eggs  and  newly 
hatched  larvae  are  easily  killed  even  with  the  weakest  strengths  used. 
The  point  of  difficulty  is  to  secure  a  treatment  which  will  penetrate  the 
cottony  masses.  The  experiments  must  be  considered  indicative  at 
best,  but  they  show  that  kerosene  emulsion  twenty  per  cent  or  more  in 
strength,  and  fhe  soaps  at  the  rate  of  one  pound  to  two  gallons  or 
stronger,  will  probably  be  effective.  These  insecticides  cannot,  of 
course,  be  used  as  a  spray  on  the  foliage.  •  It  will  be  necessary  to  apply 
them  by  means  of  a  sponge  or  brush. 

To  Sum  Up  . — Summer  treatments  in  practical  experience  have 
proved  a  disappointment,  and  must  be  considered  a  makeshift  at  best. 
If  they  become  necessary,  it  will  be  better  to  combine  two  methods. 
As  soon  as  the  cottony  masses  appear,  or  certainly  before  the  eggs  have 
hatched  in  large  numbers,  trim  out  and  promptly  burn  the  infested 
twigs  and  such  limbs  as  may  be  removed  without  seriously  marring  the 
appearance  of  the  tree.  The  remaining  masses  should  then  be  thorough¬ 
ly  soaked  with  a  strong  kerosene  emulsion  or  soap  solution  not  less 
than  one  pound  to  two  gallons  in  strength,  the  insecticides  being  ap¬ 
plied  with  a  brush  or  sponge. 

Winter  Treatment. — During  1903  and  1904  the  writer  conducted 
a  series  of  experiments  in  the  parks  of  Denver  under  the  direction  of 
Prof.  Gillette,  and  with  the  consent  and  assistance  of  the  park  author¬ 
ities.  Since  these  were  published  in  detail  with  the  Proceedings  of  the 
Association  of  Economic  Entomologists  (Bu.  of  Entom.  Bui.  52)  they 
will  be  but  briefly  reviewed  here. 

Preliminary  laboratory  experiments  conducted  during  January, 
1903,  in  which  lime  sulfur  salt,  kerosene  emulsion,  and  hard  whale  oil 
soap  were  used  showed  little  or  no  benefit  from  the  first  substance. 
Kerosene  emulsion  killed  satisfactorily  when  twenty-five  or  more  per 
cent  in  strength.  The  next  application  was  twelve  and  one  half  per 
cent  in  strength  and  did  not  seem  to  be  effective.  Hard  whale  oil  soap 
one  pound  to  one  gallon  worked  well,  killing  all  exposed  scales.  The 
weaker  strengths  did  not  show  an  appreciable  value.  These  experi¬ 
ments  were  repeated  a  week  later,  with  practically  the  same  results, 
except  that  the  whale  oil  soap  did  not  furnish  such  favorable  data. 

The  following  winter  two  series  of  experiments  were  conducted  in 
Curtis  park,  Denver.  In  the  first,  kerosene  emulsion  killed  satisfactor¬ 
ily  as  low  as  twelve  and  one  half  per  cent  kerosene.  Tobacco  stem 
decoctions  were  entirely  inefficient.  Bowker’s  tree  soap  at  two  pounds 
to  one  gallon  shriveled  the  scales;  at  one  pound  to  two  gallons,  killed 
two-thirds.  Much  to  my  regret,  the  test  of  one  pound  to  one  gallon 
was  overlooked  in  checking  up.  This  was  unfortunate  because  this 
insecticide  promised  to  be  more  useful  than  any  of  the  so.aps  previously 
used. 

In  the  second  series,  kerosene  emulsion  again  killed  as  high  as 
ninety-four  per  cent  when,  only  twelve  per  cent  kerosene  in  strength. 
Lime  sulfur  salt  was  again  a  total  failure.  Hard  whale  oil  soap  at  one 
pound  to  one  gallon  killed  ninety-eight  per  cent  of  the  scales. 

As  a  result  of  this  work  kerosene  emulsion,  one-sixth  kerosene,  was 


15 


THE  COTTONY  MAPLE  SCALE 

/  / 

recommended  and  used  in  the  parks  of  Denver.  In  July,  1905,  I  care¬ 
fully  examined  Fuller  park  which  had  been  treated  in  this  way  and 
was  surprised  to  find  it  clean.  Not  more  than  a  dozen  of  the  cottony 
masses  were  to  be  found  and  there  wrere  practically  no  scales  on  the 
leaves.  A  reexamination  of  the  same  park  in  January,  1906,  however, 
showed  that  almost  every  tree  was  infested  with  a  few  scattering 
females,  which  proved,  I  think,  that  the  eradication  of  the  scale  is  a 
practical  impossiblity. 

The  climate  of  Denver  is  much  drier  than  that  found  in  most 
parts  ol  the  insect’s  range.  The  last  set  of  experiments,  however,  were 
conducted  during  a  wet  period,  but  the  results  did  not  appear  to  be 
seriously  affected.  Mr.  Braucher  writes  me  that  kerosene  emulsion 
has  been  used  in  the  Chicago  parks  about  twenty  per  cent  in  strength 
with  most  excellent  results. 

The  winter  treatment  is  the  ideal  one  from  a  number  of  considera¬ 
tions.  The  insects  are  more  easily  reached,  for  the  twigs  and  limbs  are 
exposed.  Insecticides  may  be  used  in  sufficient  strength  to  kill  with¬ 
out  injury  to  the  tree.  The  hibernating  females  are  generally  on  the 
under  sides  of  the  limbs  and  most  abundant  on  the  lower  branches, 
which  makes  the  application  more  easy.  The  amount  of  insecticide 
required  is  less  than  half  what  it  would  be  in  summer. 

To  Summarize. — The  cottony  maple  scale  may  be  controlled  by  a 
winter  treatment  of  kerosene  emulsion  fifteen  per  cent  or  greater  in 
strength,  and  probably  by  whale  oil  soap  at  the  rate  of  one  pound  to  one 
gallon.  It  may  be  necessary  to  use  a  higher  percentage  of  kerosene 
where  the  climatic  conditions  are  unfavorable.  Eradication  of  the 
scale  is  not  to  be  expected  and  only  such  trees  and  areas  should  be 
treated  as  are  threatened  with  serious  injury. 

Too  great  stress  cannot  be  laid  on  the  thoroughness  of  the  work. 
The  tree  should  be  treated  from  both  sides  and  from  beneath  each 
limb.  After  treatment  each  tree  should  be  carefully  inspected  and  the 
missed  spots  “ touched  up.” 

The  kerosene  emulsion  should  be  carefully  made.  It  is  better  to 
use  more  soap  than  the  ordinary  formula,  since  soaps  vary  somewhat 
in  emulsifying  powers  and  the  satisfaction  of  a  good  emulsion  more 
than  repays  the  slight  extra  cost.  During  1906,  the  Denver  park 
authorities  used  in  part  a  soft  naptha  soap.  Twigs  which  had  been 
treated  with  this  emulsion  were  sent  to  this  office  and  examination 
showed  all  the  insects  to  be  dead. 


16 


BULLETIN  116 


LITERATURE 

1854 — Rathvon.  Pennsylvania  Farm  Journal.  Yol.  IV,  256-258.  Original  description  with 
figures.  As  COCCUS  INNU  MERABILIS. 

1859--Fitch.  Transactions,  N.  Y.  State  Agricultural  Society.  Yol.  XIX,  775-776.  Redescribed 
as  LECANIUM  ACERICORTICIS. 

1869— Walsh  and  Riley.  American  Entomologist.  Yol,  I,  14.  Redescribed  as  LECANIUM 
ACERICOLA  with  which  it  was  confused. 

1876— Thomas.  Prairie  Farmer.  July  22,  1876. 

1876 — Putnam.  Proceedings  of  the  Davenport  Acad,  of  Nat.  Sci.  Yol.  I,  37.  As  LECANIUM 
ACERICOLA. 

1876—  Clover.  Report  of  the  U.  S.  Commissioner  of  Agr.,  p.  44.  As  LECANIUM  ACERICOR¬ 
TICIS. 

1877 —  Putnam.  Transactions  Iowa  Horticultural  Society.  Vol.  XII,  317-324.  As  LECANIUM 
ACERICOLA. 

1878— --Miss  Smith.  Seventh  Report.  Insects  of  Ill.,  pp.  120-131.  Figures. 

1879—  Putnam.  Proceedings  of  the  Davenport  Acad.  Nat.  Sci.,  Yol.  II,  293-347.  Most  thorough 
account  of  the  life  history,  with  two  plates.  Restores  name  of  INNUMERABILIS  and 
transfers  species  so  the  genus  PULVINARIA. 

1882 —  Osborn.  Transactions  Iowa  State  Hort.  Soc.,  Yol.  XVII,  209-211. 

1883 —  Comstock.  Second  Report.  Cornell  Univ.  Exp.  Sta.,  p.  137. 

1834— Forbes.  Fourteenth  Report  of  the  State  Entomologist  of  Ill.,  pp.  103-109.  Life  History. 
Preliminary  experiments  with  insecticides. 

1884—  Riley.  Report  U.  S.  Commissioner  of  Agr.,  pp.  350-355.  Synonomy.  Life  history.  Food 
.  plants.  Mode  of  spreading.  Enemies. 

1889—  Lintner.  Sixth  Report  N.  Y.  State  Entomologist,  pp.  141-147.  Description.  Life  his¬ 
tory.  Remedies.  Bibliography. 

1890—  Riley  and  Howard.  Insect  Life.  Vol.  Ill,  125. 

1890 — Packard.  Fifth  Report  U.  S.  Entom.  Com.  pp.  412-416. 

1893— Hopkins.  W.  Va.  Agr.  Exp.  Sta.,  p.  229. 

1893— Piper.  Washington  (State)  Exp.  Sta.  Bui.  7,  pp.  123-125.  Life  history  of  the  form  OCCI- 
DENTALIS. 

1900— Howard.  Div.  Entom.  U.  S.  Dep.  Agr.  Bui.  22  (n.  s.)  8-16.  Life  history.  Parasites. 

1905— H.  E.  Weed.  Bureau  of  Entom.  U.  S.  Dept.  Agr.  Bui.  52,  pp.  88-91.  Conditions  in  the 
Chicago  Parks. 

1905— Johnson.  Bureau  of  Entom.  U.  S.  Dept.  Agr.  Bui.  52,  pp.  85-86.  Experiments  with 
winter  spraying. 

1905— Smith.  N.  J.  Agr.  Exp.  Sta.  Bui.  181,  pp.  12-15. 

1905— Sanders.  Bureau  of  Entom.  U.  S.  Dept.  Agr.  Cir.  64. 

1905—  Gossard.  Florida  Agr.  Exp.  Sta.  Bui.  79,  p.  313.  On  pecans.  Life  history  notes. 

1906—  Cotton.  Ohio  Dept.  Agr.  Orchard  and  Nursery  Inspection  Bui.  7,  p.  34.  Life  history. 
Bibliography. 


University  m  UUnois 

library 


Bulletin  1  1  7 


January  1907 


The  Agricultural  Experiment  Station 

- 

OF  THE 

*  f 

Colorado  Agricultural  College 


THE  COLORADO  POTATO  INDUSTRY 


BY 


E.  R.  BENNETT 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
FORT  COLLINS,  COLORADO 
•  1907 


The  Agricultural  Experiment  Station 

FORT  COLLINS,  COLORADO 


THE  STATE  BOARD  OF  AGRICULTURE 


Hon.  P.  F.  SHARP,  President , 
Hon.  HARLAN  T ROMAS,  - 
Hon.  JAMES  L.  CHATFIELD, 
Hon.  B.  U.  DYE, 

Hon.  B  F.  ROCKAFELLOW, 
Hon.  EUGENE  H.  GRUBB  - 
Hon.  R.  W.  CORWIN  - 
Hon.  A.  A.  EDWARDS,  -  - 


Term 
Expires 
Denver.  1907 
Denver.  1907 
-  Gypsum.  1909 

Rocky  Ford.  1909 

Canon  City.  1911 

Carbondale  1911 
Pueblo.  1913 
-  Fort  Collins.  1913 


Governor  HENRY  A.  BUCHTEL, 
President  BARTON  O.  AYLESWORTH, 


|  ex-officio. 


Executive  committee  in  charge. 

P.  F.  SHARP,  Chairman.  ~ 

B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS. 


STATION  STAFF 


L.  G.  CARPENTER,  M.  S.,  Director 
C.  P.  GILLETTE,  M.  S., 

W.  P.  HEADDEN,  A.  M.,  Ph.  D.,  - 

WENDELL  PADDOCK,  M.  S  ,  - 
W.  L.  CARLYLE,  M.  S.,  - 

G.  H.  GLOVER,  M.  S.,  D.  V.  M., 

W.  H.  OLIN,  M.  S.,  - 

H.  M.  COTTRELL,  M.  S.,  - 

R.  E.  TRIMBLE,  B.  S., 

F.  C.  ALFORD,  M.  S., 

EARL  DOUGLASS,  M.  S., 

S.  ARTHUR  JOHNSON,  M.  S., 

B.  O.  LONGYEAR,  B.  S., 

E.  B.  HOUSE,  M.  S., 


-  Irrigation  Engineer 

-  Entomologist 

Chemist  ' 
Horticulturist 
Agriculturist 

-  Veterinarian 
-  Agronomist 

Animal  Husbandman 
Assistant  Irrigation  Engineer 
Assistant  Chemist 
Assistant  Chemist 
Assistant  Entomologist 
Assistant  Horticulturist 
Assistant  Irrigation  Engineer 
Assistant  Agronomist 
Valley,  Rockyeord 
Potato  Investigations 

Grand  Junction. 

-  Field  Horticulturist 

-  Field  Entomologist 


Field  Agent,  Arkansas 


F.  KNORR,  -  -  - 

P.  K.  BLINN,  B.  S., 

E.  R.  BENNETT,  B.  S.,  - 

Western  Slope  Fruit  Investigations 

O.  B.  WHIPPLE,  B.  S.,  - 

E.  P.  TAYLOR,  B.  S.,  - 


OFFICERS 

President  BARTON  O.  AYLESWORTH.  A.  M.,  LL.  D. 

L.  G.  CARPENTER,  M.  S.,  -  --  --  --  -  Director 

A.  M.  HAWLEY,  .  Secretary 

MARGARET  MURRAY,  -  Clerk 


THE  COLORADO  POTATO  INDUSTRY. 


A  Preliminary  Report  Based  on  One  Season’s  Study,  Partly 
Aided  by  State  Appropriation  of  1905 


E.  R.  BENNETT 

The:  Potato  Industry  or  Colorado  has  a  number  of  pecul¬ 
iarities.  The  total  yield  of  the  state  (8,000,000  bu.)  as  com¬ 
pared  with  some  of  the  other  great  potato  producing  states  is  not 
large.  In  the  East  the  great  yield  of  potatoes  comes  not  from  any 
one  area  but  for  the  most  part  from  small  acreages  on  each  of  the 
many  small  farms  over  the  whole  of  a  state.  In  Colorado  the  po¬ 
tatoes  are  grown  only  in  certain  restricted  and  well  defined  districts. 
On  these  areas  potatoes  are  the  most  important  product  and  the 
other  crops  are  an  adjunct  to  or  an  element  in  the  system  in  the 
preparation  of  the  land  for  this  crop.  It  is  not  an  uncommon 
thing  in  these  districts  to  see  fields  of  from  forty  to  one  hundred 
acres  of  potatoes  on  farms  of  a  quarter  section. 

The  problems  confronting  the  growers  in  this  State,  as  to 
cultural  methods,  insect  pests  and  fungous  diseases,  are  also  radi¬ 
cally  different  from  those  of  the  Eastern  States.  Many  of  the 
fertile  irrigated  tracts  do  not  produce  potatoes  successfully,  though 
they  are  near  and  similar  in  most  respects  to  the  so  called  potato 
districts.  Why  this  is  so  has  not  so  far  been  satisfactorily  explain¬ 
ed.  The  writer  has  spent  the  past  summer  in  studying  the  con¬ 
ditions  and  methods  under  which  the  potato  is  grown  in  some  of 
the  more  successful  districts  and  comparing  the  methods  employed  at 
different  places.  Of  the  potato  producing  sections  of  the  State,  the 
irrigated  land  surrounding  Greeley  known  as  the  Greeley  District, 
the  water  shed  between  the  Arkansas  and  the  Platte  Rivers  known 
as  the  Arkansas  Divide,  a  small  section  of  the  San  Luis  Valley,  the 
Valley  of  the  Roaring  Fork  of  which  Carbondale  is  the  center  and 
the  Uncompahgre  Valley  are  the  most  important.  A  few  other 
small  mountain  valleys  produce  a  limited  quantity  for  the  local 
mining  trade. 

The  Greeley  District  exceeds  all  the  others  as  to  area  and 
amount  of  potatoes  produced.  It  is  about  twenty  miles  long  from 
northwest  to  southeast  and  twelve  or  fifteen  miles  wide  at  its 
greatest  width.  It  includes  about  200,000  acres  of  land,  though 
probably  not  more  than  one-eighth  of  this  tract  is  ever  put  in  pota¬ 
toes  at  any  one  time.  The  total  yield  per  year  of  this  tract  is  from 
9,000  to  14,000  cars  or  4,000,000  to  6,000,000  bushels. 

Comparatively  few  varieties  of  potatoes  are  grown  in  Colo¬ 
rado.  Nearly  all  the  known  varieties  have  been  tried  at  one  time  ' 


4 


The  Colorado  Experiment  Station. 


or  another  and  only  a  few  have  proved  profitable.  The  districts 
differ  somewhat  in  the  varieties  grown  owing  partly  to  the  market 
demands  and  partly  to  the  difference  in  soils,  elevation  and  length 
of  seasons  of  the  different  places. 

THE  POTATO  INDUSTRY 

The  GrEEEEy  District.  Potatoes  have  been  grown  in  this 
district  since  the  foundation  of  the  Union  Colony  in  1870.  At  first 
the  bottoms  of  the  Big  Thompson  produced  the  most,  then  the 
“blight,”  probably  Rhizoctonia.  became  so  bad  there  that  practi¬ 
cally  none  have  been  grown  for  several  years.  After  the  Big 
Thompson  bottoms  began  to  fail  as  a  potato  producing  section, 
they  were  grown  in  and  near  the  town  to  the  south  of  Greeley. 
Then  the  blight  became  so  bad  that  few « could  be  raised 
in  and  around  town  which  is  mostly  on  the  Laurel*  sand  loam 
of  the  river  bottom.  As  the  country  north  and  east  of  town 
became  broken  up,  the  industry  was  given  a  new  impetus. 
As  the  cultivated  area  grew  the  production  of  potatoes 
increased  but  was  limited  both  as  to  area  of  land  devoted  to  potato 
growing,  and  yield,  till  alfalfa  was  brought  in  as  a  part  of  the  re¬ 
gular  rotation  about  1886.  Previous  to  that  time  alfalfa  had  been 
grown  to  some  extent  but  it  was  not  thought  possible  to  break  it 
up  successfully.  From  1886  on,  the  yield  of  potatoes  increased  and 
potato  growing  as  an  industry  became  one  of  the  leading  occupa¬ 
tions  of  the  farmers  north  and  east  of  the  town.  Mr.  Boyd  in  his 
“History  of  Greeley”  written  in  1890  says:  “the  shipments  for  the 
past  five  years  from  the  Greeley  District  have  been  from  1,000  to 
1,800  cars  a  year.”  Now  the  shipments  are  from  8,000  to  14,000 
cars. 

The  blight  (Rhizoctonia)  has  given  trouble  more  or  less  from 
the  beginning.  The  Colorado  potato  beetle  has  caused  some  loss 
at  times.  Mr.  Boyd  says  in  his  history  of  Greeley:  “In  1889, 
fourteen  thousand  pounds  of  Paris  Green  were  sold  at  Greeley  and 
Eaton  for  spraying  potato  vines  for  the  striped  potato  beetle.” 
Locusts  have  occasionally  caused  some  damage.  On  the  whole, 
adverse  conditions  have  been  fewer  than  in  most  potato  growing 
sections  of  the  United  States  and  the  growth  of  the  industry  has 
been  normal  and  constant. 

The  history  of  the  other  potato  districts  of  Colorado  is  simi¬ 
lar  to  that  of  Greeley. 

The  Carbondale  District.  Potatoes  have  been  grown  in  the 
Carbondale  District  to  some  extent  since  its  early  settlement. 
Growing  potatoes  as  a  commercial  industry,  however,  did  not  begin 
till  within  the  last  eight  or  ten  years.  At  present  the  production 

*U.  S.  Department  of  Agriculture,  Bureau  of  Soils,  1904. 


The  Colorado  Potato  Industry. 


5 


is  limited  only  by  the  amount  of  irrigated  land  on  the  mesas  and 
in  the  valleys  of  the  Roaring  Fork  and  Crystal  Rivers.  The  soil 
and  climate  of  these  valleys  are  admirably  adapted  to  the  growth 
of  potatoes.  Owing  -to  the  high  elevation  and  the  proximity  of 
high  mountains,  this  district  has  a  shorter  growing  season  than  the 
Greeley  District  and  potatoes  are  planted  correspondingly  earlier. 
The  soil  is  for  the  most  part  a  red  or  blackish  sandy  loam  on  the 
mesas  with  a  somewhat  gravely  soil  in  the  river  bottoms. 

The  methods  of  culture  are  similar  to  those  practiced  in  the 
Greeley  District.  Alfalfa  is  rotated  with  grain  and  potatoes.  One 
difference  in  practice  is  that  seed  is  planted  closer.  The  hills 
there  are  nine  to  twelve  inches  apart  instead  of  thirteen  to  fifteen 
inches.  The  rows  are  also  a  little  closer  together  being  from 
thirty  to  thirty-six  inches  apart  instead  of  thirty-eight  or  forty. 

Few  places  can  compete  with  the  Carbondale  District  either 
in  yield  per  acre  or  in  quality  of  the  product.  The  yields  per  acre 
vary  on  the  different  ranches  according  to  the  natural  conditions 
of  the  soil  and  the  fertilizers  and  methods  of  cultivation  used  but 
a  high  average  yield  is  maintained. 

Here  as  at  Greeley  nearly  all  the  potatoes  raised  are  of  the 
late  varieties.  Early  potatoes  do  not  yield  sufficiently  well  to  pay, 
nor  come  early  enough  in  the  season  to  bring  the  maximum  price 
of  early  potatoes.  The  most  popular  variety  is  the  Improved 
Peachblow,  sometimes  known  as  the  Red  or  White  McClure.  Other 
varieties  are  the  Pearl,  White  Beauty,  Carmon  No.  i  and  Challenge. 
The  output  for  the  valley  is  from  300  to  500  cars,  or  from  150,000 
to  250,000  bushels. 

Quite  a  large  per  cent  of  the  West  Slope  potatoes  find  their 
way  to  special  markets  for  hotels  and  dining  car  service.  The  re¬ 
mainder  supply  the  mountain  towns  or  are  sent  into  the  same  mar¬ 
kets  as  the  other  Colorado  potatoes. 

The  San  Euis  Valley  District.  The  culture  of  potatoes 
in  the  San  Luis  Valley  is  somewhat  different  from  that  of  the  other 
potato  districts  of  the  State.  The  crop  has  been  grown  there  since 
the  early  settlement  of  the  State.  Before  the  railroad  was  put 
through  the  valley,  potatoes  were  freighted  by  wagon  to  Lead- 
ville  and  other  mining  towns. 

Alfalfa  is  not  grown  to  any  extent  in  the  valley  but  peas  take 
its  place  in  the  rotation. 

The  soil  varies  in  different  locations  but  that  on  which  potatoes 
are  grown  is  a  dark  sandy  loam  underlaid  with  gravel.  Sub-irri¬ 
gation  is  practiced  here.  The  gravel  contains  water  at  only  a  short 
distance  from  the  surface  so  by  running  water  in  shallow  ditches 
twenty  or  thirty  feet  apart,  the  water  table  is  raised  so  that  the 
moisture  is  brought  to  the  surface. 


6 


The  Colorado  Experiment  Station. 


The  varieties  grown  are  the  Monroe  County  Prize,  Rural  N.  Y. 
No.  2,  Pearl  and  Champion.  The  yield  is  at  present  about  400 
cars.  Most  of  these  potatoes  are  marketed  in  New  Mexico  or 
Texas. 

The  tendency  toward  running  out  is  not  so  noticeable  here  or 
at  Carbondale  as  in  the  Greeley  District.  In  fact  the  same  seed 
has  been  kept  at  both  these  places  for  at  least  fifteen  years  without 
deteriorating. 

The  Divide  District.  The  Arkansas  Divide  is  the  only 
place  in  the  State  of  any  extent  where  potatoes  are  grown  without 
irrigation.  Conditions  cannot  so  well  be  controlled  and  the  yield 
is  correspondingly  less.  A  specialty  is  made  of  growing  pota¬ 
toes  for  seed  in  this  locality.  As  much  of  this  seed  is  used  in  the 
Greeley  District  the  same  varieties  are  grown. 

The  culture  given  the  crop  is  similar  to  the  other  places  ex¬ 
cept  that  more  surface  cultivation  is  necessary  to  conserve  the  limi¬ 
ted  amount  of  water  though  the  rainfall  is  considerably  in  excess 
of  other  parts  of  the  State. 

METHODS  OF  POTATO  CULTURE  IN  THE  GREELEY  DISTRICT 

Owing  to  the  character  of  western  soils,  system  of  irrigation, 
large  acreage  of  potatoes  per  farm  and  rotation  of  crops,  the  me¬ 
thods  of  potato  culture  in  Colorado  differ  somewhat  from  those  of 
other  sections  of  the  country.  At  first  the  methods  of  irrigation 
and  cultivation  best  suited  to  the  conditions  here  were  not  well 
understood  but  since  it  was  found  that  alfalfa  could  be  success¬ 
fully  broken  up  and  that  deep  cultivation  was  most  beneficial  the 
methods  have  not  changed  to  any  considerable  extent. 

There  is  a  prevailing  opinion  that  potatoes  require  a  certain 
kind  of  soil.  There  undoubtedly  is  a  relation  between  the  yield 
and  quality  of  potatoes  at  certain  places  and  the  different  soils. 
Just  what  this  relation  is,  however,  has  not  as  yet  been  success¬ 
fully  explained.  Good  yields  of  potatoes  are  produced  on  several 
different  soils  and  failures  occur  on  all  of  them. 

Soils.  The  soils  used  for  potatoes  111  the  Greeley  Potato  Dis¬ 
trict  are :  *Billings  loam,  Colorado  fine  sand,  Colorado  sand,  Bill¬ 
ings  clay  loam  and  to  a  certain  extent  Laurel  sand  loam. 

The  Billings  loam  is  a  heavy  soil  well  mixed  with  sharp  gran¬ 
itic  gravel.  It  has  a  depth  of  from  two  to  five  or  six  feet.  This 
soil  is  underlaid  with  gravel  which  gives  good  under  drainage. 
More  care  has  to  be  exercised  in  handling  this  soil  because  if 
worked  when  too  wet  or  too  dry,  it  is  more  liable  to  become  lumpy 
than  are  the  lighter  loams. 

The  Colorado  fine  sand  loam  is  intermediate  between  the 
Billings  loam  and  the  Colorado  sand.  It  is  generally  deeper  than 

*  U.  S.  D ^partm^nt  of  Agriculture,  Bureau  of  Soils,  1904. 


The  Colorado  Potato  Industry. 


7 


the  Billings  loam  and  does  not  pack  or  become  lumpy  so  easily  as 
the  latter  but  on  the  other  hand  it  contains  less  gravel.  These 
two  soils,  constitute  by  far  the  larger  part  of  the  successful  po¬ 
tato  district  north  and  east  of  the  town  of  Greeley. 

The  Billings  clay  loam  is  finer  than  either  of  the  others.  It 
has  less  gravel  and  is  so  deep  that  the  under  drainage  is  not  good. 
This  soil  occupies  narrow  strips  in  the  creek  bottoms  and  while 
it  often  produces  good  crops  of  potatoes  it  is  liable  to  serious 
attacts  of  fungous  diseases. 

The  Colorado  sand  is  coarser  in  texture,  contains  less  nitro¬ 
genous  matter  and  requires  more  water  to  produce  a  crop  but 
where  proper  rotation  of  crops  and  cultural  methods  have  been 
employed,  good  results  are  obtained. 

The  Laurel  sand  loam,  which  is  the  first  bottom  land  of  the 
Poudre  River  Valley,  is  not  very  different  from  the  other  sandy 
loams  but  in  most  places  the  water  table  is  close  to  the  surface 
and  potato  growing  on  this  soil  in  not  uniformly  successful. 

All  these  soils  contain  more  or  less  alkali  but  not  enough  in 
most  cases  to  prevent  the  development  of  plants  except  where 
water  stands  and  evaporates. 

Preparation  oe  Potato  Land.  The  preparation  of  the  land 
for  potato  growing  is  probably  the  most  important  item  of  the 
work.  The  difference  between  new  land  broken  for  potatoes,  old 
land  and  alfalfa  land  is  most  marked.  The  new  land  produces  a 
very  clean  grade  of  potatoes  but  does  not  give  so  good  a  yield  as 
land  either  preceeded  by  potatoes  or  alfalfa.  Alfalfa  land  gives 
the  largest  yields  and  is  less  liable  to  disease  than  where  potatoes 
succeed  potatoes.  The  universal  practice  is  to  rotate  so  as  to 
preceed  potatoes  with  alfalfa. 

Rotation  oe  Crops.  The  most  common  rotation  is  alfalfa  two 
or  three  years,  potatoes  two  years  or  where  beets  are  grown,  pota¬ 
toes  one  year,  and  beets  one  year,  then  grain  two  years.  Sometimes 
wheat  or  oats  are  only  grown  one  year  but  experience  has  shown 
that  in  the  majority  of  cases,  the  first  year  of  grain  following 
potatoes  or  beets  produces  so  much  straw  that  the  young  alfalfa 
is  smothered  out  if  grown.  The  grain,  owing  to  the  reduced 
fertility  of  the  soil,  is  not  so  large  the  second  year  and  makes 
a  better  nurse  crop  for  the  alfalfa.  Another  rotation  practiced  to 
some  extent  is  alfalfa  two  years,  potatoes  one  year,  wheat  one 
year,  potatoes  one  year,  grain,  then  alfalfa  again.  This  system 
while  not  very  generally  practiced  has  some  possibilities  in  the  way 
of  blight  control  which  will  be  spoken  of  later  in  this  report. 
The  number  of  years  alfalfa  should  be  allowed  to  grow  to  get  the 
land  in  the  best  condition  for  potatoes  is  an  open  question. 

While  by  far  the  majority  of  growers  allow  it  to  stand  but 


8 


The  Colorado  Experiment  Station. 


two  years,  it  is  the  opinion  of  some  authorities  and  many  of  the 
best  practical  farmers  that  it  would  do  most  good  if  left  tluee 
years.  Some  think  that  even  six  or  seven  years  would  be  better. 

Winter  sheep  feeding  has  changed  the  rotation  to  some  extent. 
When  enough  sheep  are  fed  to  produce  a  good  coat  of  manure 
for  the  potato  fields,  potatoes  are  followed  with  potatoes  twice  01 
potatoes  once  and  once  with  beets.  Very  substantial  gains  in 
yield  of  both  potatoes  and  beets  have  resulted  where  manure  has 
been  used.  The  use  of  manure  on  land  here  as  well  as  in  the 
Eastern  states  is  cumulative  in  its  effects  and  benefits  particularly 
the* heavy  soils  in  two  ways.  The  physical  condition  of  the  soil 
is  improved  by  being  made  more  porous  and  friable  so  that  it 
will  hold  moisture  better  and  of  course,  plant  food  is  also  added 
to  it. 

Plowing.  In  the  preparation  of  the  land  for  potato  growing 
the  plowing  is  not  the  least  important.  This  is  sometimes  done 
in  the  late  fall  but  more  commonly  in  the  spring  from  the  latter 
part  of  April  to  May  15th.  Fall  plowing  gives  good  results  but 
ordinarily  time  for  doing  the  work  cannot  be  found  at  that  season 
or  the  land  may  be  too  dry  to  make  plowing  possible.  The  depth 
of  plowing  ranges  'all  the  way  from  six  to  twelve  inches  but 
nearly  as  many  plow  eight  inches  deep  as  all  other  depths  taken 
together.  The  work  is  generally  done  with  four  horses  and  a 
14-16”  plow.  When  alfalfa  is  being  broken  the  plows  used  have 
a  wide  share  so  that  all  the  alfalfa  roots  are  cut  off  at  the  bottom 
of  the  furrow. 

A  practice  that  is  to  be  commended  in  other  places  as  well 
as  on  the  irrigated  land  of  Colorado  is  that  of  following  the  plow 
immediately  with  the  smoothing  harrow.  This  is  done  partly  to 
mellow  the  soil  and  prevent  the  formation  of  lumps  but  mostly  to 
conserve  the  moisture.  Experiments  have  demonstrated  that  the 
loss  of  moisture  by  evaporation  is  much -less  where  this  is  done 
than  where  the  plowed  land  remains  for  a  time  without  harrowing. 
In  this  State  the  practice  is  to  harrow  all  the  land  that  is  plowed 
each  half-day  before  leaving  the  field. 

Harrowing  and  Leveling.  In  many  fields  scrapers  are  used 
after  the  first  harrowing  to  fill  the  hollows  and  take  down  any 
ridges  that  are  liable  to  cause  trouble  in  getting  water  evenly 
distributed  over  the  field.  The  amount  of  work  required  to  fit  the 
land  for  planting  after  the  first  harrowing  and  leveling  depends 
on  the  character  of  the  land.  With  average  loamy  soils  one  or 
two  subsequent  harrowings  are  sufficient  to  put  the  soil  in  per¬ 
fect  condition  for  planting.  If  the  soil  is  heavy  or  has  been 
packed  by  rains,  the  disk  harrow  is  used  and  followed  by  the 
smoothing  harrow. 


UMil ifif  ,i±uiu.u  i/im’iiiiJhijum iuiiHiULwwjuu :uimwiit  niiiJiniiiLiii  iL'uawumiuim 


PLATE  I.  CULTURAL  OPERATIONS. 

Furrowing.  2.  Digging.  3.  Cultivating.  4.  Planting. 


PLATE  II. 


Conveniences  for  Cutting  Seed  Potatoes.  Notice  the  Knife  in  the  Board. 


PLATE  III.  Irrigating  Potatoes — alternate  rows. 


PLATE  IV.  POTATO  CELLARS. 

2.  Exterior. 


I .  Process  of  Construction 


3 


Interior 


Thk  Colorado  Potato  Industry. 


9 


Planting.  Much  diversity  of  opinion  prevails  among  the 
growers  as  to  the  details  of  preparing  seed  and  planting.  The 
general  practice  is  to  select  seed  from  the  stock  which  is  left  over 
winter  in  the  storage  cellar  for  the  spring  market  if  home  grown 
seed  is  used.  If  not,  the  seed  is  purchased  from  the  Divide 
country,  the  mountains  or  from  the  East.  Medium  to  small  seed 
is  used  by  the  majority  of  growers.  Some  make  a  practice  of 
greening  the  seed.  That  is  the  seed  is  spread  in  a  thin  layer 
on  the  floor  of  the  dugout  a  few  weeks  before  planting  time.  The 
ventilators  and  doors  are  left  open  to  admit  the  light.  Occa¬ 
sionally  the*  potatoes  are  shoveled  over  to  give  a  uniform  expo¬ 
sure  so  that  by  planting  time  the  tubers  have  become  hardened 
and  green,  and  the  sprouts,  if  there  are  any  are  short  and  green 
instead  of  being  long,  slim  and  pale.  The  formailin  or  corrosive 
sublimate  treatment  is  seldom  used.  Cutting*  is  done  by  hand. 
The  number  of  eyes  depends  on  the  variety  as  some  varieties  of 
potatoes  have  many  eyes  while  others  have  few.  The  usual  aim 
is  to  leave  two  eyes  on  a  piece,  but  the  rule  is  not  arbitrary.  In 
fact  the  work  coming  at  the  busy  season  makes  it  necessary  to 
employ  inefficient  help  so  that  some  pieces  are  left  with  many 
eyes  while  others  have  none.  A  method  of  cutting  shown  in 
Figure  2,  Plate  I,  is  thought  to  facilitate  the  work  to  some  extent, 
fl  he  potatoes  aie  shovelled  into  a  bin  or  hopper  made  of  a  dry 
goods  box  raised  on  legs.  The  back  is  made  higher  than  the 
front  so  that  the  potatoes  will  run  down  to  the  opening.  In  the 
bottom  are  cracks  to  let  out  the  soil  that  is  shoveled  up  with  the 
potatoes.  The  cutting  is  simple.  An  old  case  knife  or  a  shoe 
knife  is  fastened  to  the  end  of  a  piece  of  plank  or  board  in  such 
a  way  that  the  potato  can  be  pushed  against  the  knife  and  fall 
from  it  into  the  basket  beneath.  The  seed  is  planted  soon  after 
cutting  as  it  is  thought  that  the  vitality  of  the  buds  rapidly  becomes 
lowered  as  the  seed  drys  out. 

Various  substances  are  used  on  the  cut  seed  that  are  sup¬ 
posed  to  be  beneficial  by  drying  the  cut  surfaces  and  preventing 
the  work  of  insects  01  fungi.  Air  slaked  lime,  flowers  of  sulphur 
and  gypsum  (land  plaster)  are  all  used  by  different  growers.  All 
these  are  used  in  the  same  way.  The  cut  seed  is  piled  on  a  floor, 
the  material  is  scattered  on  and  then  mixed  by  shoveling  the  pile 
over  till  the  dust  is  brought  in  contact  with  each  piece. 

Varities.  Very  few  early  potatoes  are  grown.  Early  var¬ 
ieties  have  frequently  been  tried  but  the  yield  is  seldom  satisfac¬ 
tory  and  the  crop  cannot  be  marketed  in  time  to  get  a  high  enough 
price  to  make  up  for  the  deficiency  in  yield.  Mammoth  White 
Pearl  leads  all  the  other  varities  in  acreage  and  generally  in 
yield.  Rural  N.  Y.  No.  2  is  second  in  popularity  and  some 


to  The:  Colorado  Experiment  Station. 

Ohios  and  Snowflakes  are  planted.  Nearly  all  the  known  vaiie- 
ties  have  been  tried  in  this  district  at  one  time  or  another  but 
none  of  them  have  been  able  to  compete  with  those  named.  The 
long*  potatoes  tend  to  become  longer  and  roughened  and  in  a  yeai 
or  two  degenerate  or  revert  to  what  is  supposed  to  be  the  ances- 
ter  of  our  present  race  of  potatoes.  Owing  to  this  tendency  for 
seed  to  “run  out”  the  same  stock  is  not  used  more  than  two  or 
three  years. 

Planting.  All  planting  is  done  by  machinery.  Among  the 
different  makes  of  planters  used  are  the  Aspinwall,  the  Evans,  the 
Superior,  the  Robins  and  the  Excelsior.  All  these  planters  require 
cut  seed.  Very  little  difference  can  be  seen  in  the  work  of  any  of 
them.  Four  horses  are  used  with  these  planters  and  five  to 
seven  acres  planted  is  considered  a  days  work.  The  rows  are 
from  thirty-six  to  forty  inches  apart,  with  a  distance  between 
plants  in  the  row  of  thirteen  or  fifteen  inches. 

Cultivation.  Very  soon  after  planting  the  first  cultivation 
is  given.  The  ridge  left  by  the  planter  shows  the  rows  so  the 
plants  do  not  need  to  be  seen.  The  object  of  the  first  cultivation 
is  two-fold.  First  the  tramping  of  the  four  horses  used  on  the 
planter  packs  the  ground  solidly.  This  needs  to  be  loosened 
to  areate  the  soil  and  prevent  loss  of  moisture  by  evaporation. 
Second  the  alfalfa  or  weeds  that  are  starting  are  killed.  For 
this  work,  four  horses  on  a  heavy  four  shovel  John  Deere  type  of 
cultivator  are  user.  The  shovels  are  set  to  run  as  deep  in  the  soil 
as  they  will  go  which  is  from  eight  to  twelve  or  thirteen  inches. 
They  are  also  set  so  as  to  throw  the  soil  toward  the  potato  rows, 
thus  beginning  the  hilling  or  ridging  process  which  is  character¬ 
istic  of  potato  culture  in  this  locality.  This  operation  leaves  the 
soil  loose  but  more  or  less  lumpy,  and  with  a  rough  uneven  sur¬ 
face,  especially  on  the  heavy  soils.  The  harrow  immediately  fol¬ 
lows  the  cultivator  to  re-establish  the  soil  mulch.  These  two 
operations  destroy  the  young  weeds  so  there  is  little  trouble  in 
keeping  the  field  clean. 

The  number  of  cultivations  depends  upon  the  weather  condi¬ 
tions  and  rapidity  of  growth  of  the  vines.  The  cultivator  is  used 
a  second  time  as  soon  as  the  plants  are  large  enough  so  that  the 
rows  can  be  easily  followed.  This  time  the  shovels  are  not  run 
quite  so  close  to  the  row  but  to  the  same  depth  unless  the  plants 
are  much  developed.  In  that  case  the  inside  shovels  are  raised 
so  as  not  to  injure  the  root  system.  Sometimes  two  cultivations 
are  all  that  are  given  but  ordinarily  a  third  follows  the  second 
by  a  week  or  ten  days  and  if  the  vines  do  not  get  too  large  or 
irrigation  become  necessary,  cultivation  is  continued.  Each  time 
the  cultivator  is  used  more  soil  is  thrown  toward  the  potato  rows 


The  Colorado  Potato  Industry.  ii 

and  the  hollow  between  the  rows  becomes  deeper,  thus  ditching 
is  more  easily  done. 

Ditching  and  irrigating  are  delayed  as  long  as  possible.  The 
rule  is  not  to  irrigate  if  it  can  be  avoided  till  the  potatoes  are  in 
bloom  or  the  tubers  set. 

Ditching.  The  ditching  is  done  with  a  narrow  double 
mold  board  plow.  Three  horses  are  attached  and  the  plow  is 
run  once  in  each  row  at  about  the  depth  of  cultivation  or  ten  to 
twelve  inches.  This  ditching  takes  the  place  of  one  cultivation 
and  if  the  ground  is  hard  or  if  the  first  irrigation  fills  the  ditches 
to  any  extent,  the  operation  is  repeated  so  as  to  make  the  ditches 
deep  enough  to  keep  the  water  below  the  surface  of  the  potato 
ridges. 

Irrigation.  .The  details  of  irrigation  depend  upon  the  size 
and  contour  of  the  field  to  be  irrigated.  Many  of  the  fields  are 
arranged  so  that  the  rows  are  from  one-fourth  to  one-half  mile 
long.  If  the  land  slopes  sufficiently  and  continuously  across  the 
field  from  the  supply  ditch,  the  problem  is  simple.  At  the  first 
application  the  water  is  turned  into  a  lateral  at  the  head  of  the 
rows.  A  canvas  dam  is  placed  in  the  lateral  so  as  to  hold  the 
water  back  and  raise  it  into  the  rows.  After  the  water  has 
run  in  these  rows  a  sufficient  length  of  time  to  thoroughly  wet 
the  soil,  the  canvas  dam  is  pulled  out  and  reset  farther  down  the 
lateral,  and  the  water  is  stopped  by  blocking  the  heads  of  the 
irrigated  rows  with  soil.  In  large  fields  the  water  is  run  in  al¬ 
ternate  rows  only. 

The  head  of  water  let  into  the  rows  depends  upon  the  slope 
and  length  of  rows.  If  the  rows  are  short  and  the  incline  steep, 
the  head  must  be  small  or  the  stream  will  reach  the  far  side  so 
quickly  that  enough  water  will  not  be  used  to  thoroughly  wet 
the  soil.  On  the  other  hand,  if  the  rows  are  long  and  the  land 
nearly  level  the  head  of  water  is  increased  so  as  to  force  it  along 
the  rows  faster,  or  a  transverse  ditch  is  cut  through  the  middle 
of  the  field  so  as  to  shorten  the  distance  that  the  water  has  to 
flow.  If  ridges  occur  in  the  field  transverse  ditches  are  run  along 
at  their  top  and  irrigating  is  done  both  ways  from  it.  When 
the  water  has  run  in  the  ditches  till  it  seeps  through  to  the  unirri¬ 
gated  row,  the  soil  is  sufficiently  wet.  At  the  second  irrigation 
the  water  is  run  in  the  rows  not  irrigated  the  first  time.  As 
the  vines  become  large,  the  irrigation  becomes  more  difficult  owing 
to  the  lodging  of  the  vines  in  the  ditches,  till  at  last  ,  considerable 
trouble  is  sometimes  experienced  to  get  the  water  through.  On 
the  other  hand  as  the  vines  grow  larger  the  soil  is  more  protected 
from  the  sun  so  that  the  evaporation  becomes  less  and  the  plants 
suffer  less  from  want  of  water. 


12 


The;  Colorado  Expe;rime:nt  Station. 


of  Trr  0F  XyATER  USED  T°  Grow  Potatoes.  The  number 
t,  A /  ca  ions  and  amount  of  water  used  per  acre  varies  with 

e  min  f°,fIlS?  T?  amT°Unt  °f  rain  falL  With  averaSe  seasons 

UD  the  nl!  r  f0r.May’  and  ear]y  July  is  sufficient  to  bring 

up  the  plants  and  grow  them  till  the  tubers  begin  to  form.  Irri- 

ren  °;r^,brn  must  b,e  cTtmued  at  intervais  of  one  week  to 

less  the  T  heKC1"0P  !S  devel°Ped-  Four  or  five  irrigations  un- 

be.  a  dlT  one  will  carry  the  crop  through.  A 

is  best  °  opinion  PfevalIs  as  t0  tlle  amount  of  water  that 
growers  hold?  ’?  -lrrl&atlnf  Potatoes.  Most  of  the  successful 
fs  iter?  c  t  lat  111  general  to°  much  rather  than  too  little  water 
show  the  Some  measurements  taken  on  the  E.  R.  Bliss  ranch 
show  the  amount  of  water  actually  used  in  growing  a  crop  of 

potatoes  both  on  alfalfa  land  and  on  old  potato  land  The  an- 

mad?  a?  folT  P°ta|°, field  wldch  was  preceeded  by  aifalfa  were 

ehveiw  of 1  Z  i  Y  257  ,  T  Water  ran  hours  with  a 

i  06  fL  l  4  5  fee  P61  SeCOncL  August  1  and  2-  27  hours  with 
1.96  feet  per  second.  August  8  and  9,  24  hours  at  2.1*1  feet  per 

n  Ml  80a  ^  l6>  30  h°UrS  at  2'37  feet  p3er  second, 

n  all  893,916  cubic  feet  of  water  was  used.  This  field  was  1218 

feet  one  way  by  639  feet  the  other.  This  gives  an  area  of 

S.T A?  “  ,  '7'88  “d  *  ^ of  ..ter  It,  i„ 

II  o  k  f  r3'/6  niches.  The  ram  fall  by  months  from  April 
till  October  was:  April,  3.04  inches;  May,  1  73 ;  June  no-  Tulv 

2-24.  tigust,  .64  and  September,  2.31,  or  11.05  inches'  The  Sep' 

Syerdida  litt7eaif  m°Stly  in,  the  Jatter  part  0f  tbe  month  and  pro- 

rainfah  ' V left  L?/  t0  6  .P°tat°  croP-  If  the  September 
a  mail  is  left  out,  the  precipitation  that  should  be  counted  as 

2faUU2  fh  the.gr0wth  of  the  cr°P  will  be  8.75  inches.  The 

used  01  the  croii  f ‘m  S,  US,  ^  inCheS  aS  *e  total  water 

three  years  TtMs  ET  ^  ?  1&d  P!‘ev,ousIy  been  in  alfalfa  for 

ee  years.  It  is  Billings  loam  soil  (clay  loam)  with  Quite  a 

lai  ge  pei  cent  of  sharp  granitic  gravel.  The  soil  is  about  two 
drainage  The  field eeP’  with  gravel>  80  it  has  good 

•»  r-/»d8sn"„c&ka^: 

atoes  June  1st.  The  yield  of  Pearls  on  this  field  was  above  nn 
sacks  pei  acre  which  is  near  the  maximum  for  the  season.  5 

The  field  adjacent  to  this  one  which  had  grown  potatoes  the 
year  before  gave  somewhat  different  results  as  to  amount  of  water 
required,  yield  of  potatoes  and  time  of  ripening 

d  he  applications  on  this  field  were  iust  nrevimie  .u 
on  the  alfalfa  land  potato  field.  The  first IT  £uS  m 
a  discharge  of  4.05  feet  per  second  and  the  second  18  hours  a 
1.96  feet  per  second,  the  third  16  hours  at  2.31  feet  pe.  second 


The  Colorado  Potato  Industry. 


i3 


and  the  fourth  24  hours  at  2.37  feet  per  second  or  a  total  of  668,232 
cubic  feet  of  water.  This  field  was  1,300  feet  long  by  660  feet 
wide  which  gives  an  area  of  858,000  square  feet  or  19.74  acres, 
and  a  depth  of  water  over  the  field  of  9.35  inches.  The  difference 
in  the  irrigating  water  between  the  old  potato  land  and  the  alfalfa 
land  was  *4.41  inches.  This  field  was  planted  just  previously 
to  the  alfalfa  field  and  the  potatoes  ripened  (or  the  vines  died 
from  Rhizoctonia)  about  two  weeks  earlier.  The  yield  was 
about  130  sacks  per  acre  as  against  something  over  150  sacks  for 
the  alfalfa  land.  Frequently  a  greater  difference  than  this  results 
between  alfalfa  land  for  potatoes  and  land  preceeded  by  other 
crops.  It  would  hardly  seem  that  the  difference  comes  from  the 
amount  of  plant  food  in  the  soil  for  after  potatoes  have  been 
grown  011  soil  even  three  years,  the  cereals  grown  on  it  will  pro¬ 
duce  heavy  crops. 

The  difference  in  the  amount  of  water  can  be  attributed  to 
the  physical  condition  of  the  soil  in  the  two  fields.  The  decay¬ 
ing  alfalfa  stems  and  roots  make  the  land  more  porous  and  the 
first  irrigation  particularly  takes  more  Water  to  fill  the  soil. 

Harvesting  the  Crop.  The  potato  harvesting  is  done  so 
far  as  possible  with  machinery.  The  diggers  used  are  the  Peter 
Brown  and  the  Doudon  type  of  machines.  With  these  the  potatoes 
are  plowed  out  and  elevated  over  carriers  that  separate  the  tubers 
from  the  soil  and  leaves  them  scattered  on  the  ground.  Four  or 
six  horses  are  used  on  these  machines.  One  machine  will  keep 
from  ten  to  fifteen  men  busy,  depending  on  the  yield,  picking, 
sacking  and  hauling  from  the  field.  While  these  machines  are 
not  perfect,  they  leave  the  potatoes  well  separated  from  the  soil, 
providing  the  soil  is  not  too  wet  nor  the  vines  and  weeds  to  numer¬ 
ous.  Sometimes  a  harrow  is  run  over  the  field  before  digging  to 
knock  down  and  tear  out  some  of  the  vines  that  would  clog  the 
digger.  When  several  rows  are  dug  (depending  on  the  number 
of  pickers)  the  picking  and  sacking  begins.  The  potatoes  are 
picked  in  baskets  and  dumped  onto  the  sorter.  This  machine  is 
simply  a  frame  on  runners  to  which  a  horse  may  be  attached  to 
keep  it  alongside  the  pickers.  On  this  frame,  two  seives,  made 
of  heavy  wire,  are  placed,  slanting  to  the  back  so  that  the  large 
potatoes  that  will  not  go  through  the  upper  seive  roll  down  into  a 
sack.  The  smaller  ones  go  through  onto  the  lower  seive  which  is 
a  finer  mesh  and  roll  into  another  sack  while  the  very  small  potatoes 
and  soil  fall  through  the  second  seive  to  the  ground. 

If  the  potatoes  are  to  go  direct  to  the  market,  the  sacks  are 
filled  and  set  off  on  the  ground.  A  man  follows  the  sorter  and 
with  a  needle  and  coarse  twine  closes  the  sacks  by  sewing  up  the 
top.  The  filled  sacks  are  then  loaded  onto  wagons  and  hauled 


H 


The  Colorado  Experiment  Station. 


to  the  markets.  These  sacks  are  made  of  coarse  burlap  and  hold 
from  no  to  120  pounds  of  potatoes.  All  potatoes  are  marketed 
in  this  way.  Much  expense  in  handling-  and  loss  fiom  stoiing 
is  avoided  by  this  system  of  marketing  direct  from  the  field  but 
on  the  other  hand,  the  markets  are  often  over  supplied  and  the 
price  reduced,  by  throwing  such  a  large  quantity  of  potatoes  onto 
the  market  at  one  time.  With  the  present  conditions,  however, 
the  marketing  of  a  large  per  cent  of  the  ciop  from  the  field  is 
necessary  owing  to  lack  of  storage  capacity  on  the  farm.  If  the 
potatoes  are  to  be  stored  in  the  “dugouts”  or  potato  cellars,  the 
sacks  are  only  partly  filled  in  the  field  then  taken  to  the  dugout 
and  emptied  into  bins. 

The  Storage  House.  The  dugout  or  storage  cellar  is  dis¬ 
tinctly  a  dry  clfmate  or  western  feature.  While  its  principles 
of  construction  would  not  adapt  it  to  places  of  heavy  lainfall,  it 
is  not  only  cheap  but  most  efficient  as  a  storage  place  foi  potatoes 
and  other  root  crops  in  this  climate.  Being  surrounded  by  soil 
on  all  sides,  a  nearly  constant  temperature  is  easily  maintained. 
The  loss  from  shrinkage  by  evaporation  is  also  less  than  in  ordinary 
cellars. 

The  construction  of  the  dugout  is  simple.  An  excavation 
is  made  in  the  ground  of  the  required  dimensions  for  the  cellar 
and  of  a  sufficient  depth  to  give  soil  for  covering  the  top.  A 
frame  of  posts,  timbers  and  rafters  is  then  made  as  for  a  building 
This  frame  is  covered  with  wire  netting  or  brush.  Over  this  two 
or  three  feet  of  straw  is  placed  and  this  covered  with  soil  to  a 
depth  of  six  to  twelve  inches.  Figure  1,  Plate  IV,  shows  the  method 
of  covering  the  cellar  with  soil.  Ventilator  shafts  are  put  in  at 
regular  intervals  to  give  air  circulation  and  keep  the  temperature 
from  rising  too  high.  Most  of  these  dugouts  have  an  alley  through 
the  center  with  doors  at  either  end  so  that  the  wagon  may  be 
driven  through.  Double  doors  with  a  dead  air  space  between  are 
used  as  a  protection  against  frost. 

These  dugouts  are  often  filled  to  their  full  capacity  in  the 
fall  to  hold  the  crop  for  a  rise  in  price.  If  they  are  stored  while 
the  weather  is  yet  warm  the  ventilators  and  doors  are  left  open 
nights  to  give  a  circulation  of  cold  air  and  closed  during  the  heat 
of  the  day.  In  this  way  the  bins  are  gradually  cooled  down  and 
by  giving  close  attention  to  the  temperature  the  whole  mass  is 
kept  as  cool  as  possible  without  danger  from  frost.  During  the 
winter  considerable  care  has  to  be  exercised  to  prevent  the  temp¬ 
erature  of  the  dugout  from  rising  from  the  heat  developed  by  the 
stored  potatoes.  This  is  regulated  by  opening  and  closing  ‘the 
ventilator  shafts  as  the  case  demands. 


The  Colorado  Potato  Industry.  15 

MARKETS 

The  position  which  Colorado  occupies  in  respect  to  markets 
is  one  of  the  most  important  factors  in  making  the  industry  pro¬ 
fitable.  Her  geographical  position  is  such  that  advantage  can  be 
taken  of  a  shortage  of  crop  either  east  or  west  of  the  mountains. 
And  at  the  same  time  she  is  far  enough  away  from  the  potato  pro- 
•  ducing  central  states  to  avoid,  to  a  great  extent,  the  glutted  mar¬ 
kets  that  frequently  occur  when  large  crops  prevail  in  the  Miss¬ 
issippi  valley  and  in  the  Cake  Region.  The  cities  of  the  east 
slope  of  the  Rockies  with  Texas  and  New  Mexico  ordinarily  get 
the  large  share  of  the  crop  but  not  infrequently  the  Pacific  Coast, 
Central  States  and  even  New  York  and  Boston  are  markets  for 
the  Greeley  product.  Practically  all  Colorado  potatoes  are  put  on 
the  market  in  sacks.  This  system  is  somewhat  more  expensive 
than  shipping  loose  in  the  cars  as  sacks  cost  from  $6.50  to  $8.00 
per  hundred.  The  system  of  sacking,  however,  has  an  advantage 
in  that  less  time  is  required  in  handling  the  crop  and  the  system 
is  growing  in  favor  in  all  the  potato  growing  sections. 

POTATO  PESTS 

The  insect  enemies  and  diseases  of  potatoes  of  Colorado  are 
so  different  from  those  of  the  eastern  states  that  the  work  done 
there  on  this  subject  is  of  little  value  to  the  Colorado,  potato 
grower. 

Insects.  The  striped  or  Colorado  potato  beetle  is  a  native  of 
this  state,  yet  the  damage  done  by  this  beetle  is  now  ordinarily  so 
slight  that  no  attention  is  given  it  by  the  growers.  The  flea  beetle  is, 
however,  a  serious  pest..  Comparatively  little  is  known  of  the  life 
history  of  this  insect.  There  are  several  species  similar  in  gen¬ 
eral  appearance  that  do  more  or  less  damage.  The  worst  one  is 
the  black  flea  beetle  (Epitrix  cucumeris).  The  last  of  May  or 
the  first  of  June  these  little  flea-like  beetles  may  be  seen  in  quan¬ 
tities  feeding  on  the  weeds  along  the  fences  and  ditch  banks. 
They  are  black  or  dark  brown,  shiny  and  about  one-tenth  of  an 
inch  long.  When  disturbed,  the  insect  jumps  and  disappears,  a 
trick  that  gives  it  the  name  of  “flea  beetle.”  How  they  pass  the 
winter  is  not  known.  Their  presence  is  most  noticeable  by  the 
appearance  of  the  foliage  that  has  been  eaten,  as  the  numerous 
little  holes  or  light  spots  on  the  leaves  of  potatoes  as  well  as  to¬ 
matoes  and  the  cucurbits  are  due  to  them.  These  perforations 
in  the  foliage  injure  the  plant  by  rducing  the  leaf  surface  and 
also  by  giving  entrance  into  the  leaf  of  various  plant  diseases. 
Just  how  much  the  yield  of  tubers  is  cut  down  by  this  injury  to 
the  foliage  is  difficult  to  estimate.  Later  in  the  season  the  insect 
deposits  eggs  on  the  underground  stems  of  the  plants.  The  lar- 


16  The  Colorado  Experiment  Station. 

vae  soon  appear  as  very  small  white  worm-like  bodies  on  the 
potatoes  or  underground  stems.  These  larvae  are  slender  and 
from  an.  eighth  to  one-fourth  of  an  inch  long.  If  tubers  are  care¬ 
fully  taken  from  the  soil  early  in  the  season  where  these  insects 
are  prevalent,  the  larvae  may  be  found  burrowing  into  the  tuber 
about  one-third  of  the  body  being  inside.  At  a  casual  glance 
they  appear  not  unlike  short  root  hairs  growing  from  the  surface. 
The  injury  caused  by  this  insect  produces  the  pimply  effect  so 
often  seen  in  potatoes  on  the  market  and  is  often  confused  with 
or  may  be  classed  as  one  of  the  forms  of  scab.  No  practical  re¬ 
medy  is  known  for  this  insect  in  this  state.  Spraying  with  Bor¬ 
deaux  mixture  and  arsenites  destroyes  or  repells  them  but  the  ex¬ 
pense  of  application  of  this  remedy  prohibits  its  use  under  the 
system  of  growing  used  here.  When  potato  planting  is  delayed 
till  June  first,  the  injury  to  the  foliage  is  avoided  to  some  extent- 
for  by  the  time  the  plants  are  up  the  insects  have  sought  other 
feeding  grounds. 

This  insect  is  quite  generally  distributed  over  the  country 
but  is  more  prevalent  in  some  places  than  in  others  and  is  also 
more  numerous  some  seasons  than  others.  The  past  season  they 
have  been  particularly  numerous,  probably  owing  to  the  preceed- 
ing  mild  winter. 

Not  infrequently  scabby  or  injured  potatoes  are  infested  with 
numerous  small  white  worms  so  that  there  is  quite  a  general 
opinion  that  the  scabbiness  or  injury  is  caused  by  them.  This  is 
not  usually  the  case.  The  injury  or  scab  is  caused  by  some  other 
agent  and  the  worms,  which  are  saprophitic,  work  in  the  dead  tissue 
and  by  so  doing  are  credited  with  the  damage.  When  earth  worms 
are  particularly  plentiful  the  potatoes  may  be  made  dirty  as  a  re¬ 
sult  of  the  worms  crawling  over  them  and  leaving  a  slime  to 
which  the  soil  sticks. 

Fungous  Diseases.  The  fungous  diseases  of  Colorado  potatoes 
differ  widely  from  those  which  cause  the  serious  losses  of  the  East. 
Early  blight  (alternaria)  can  be  found  but  so  far  as  is  known  little 
or  no  damage  has  resulted  from  it.  The  late  blight  (Phytophthora 
infestans)  has  never  appeared  at  all. 

Corticium  Vagum  B.  &  C.  (Rhizocionid) .  The  serious  fun¬ 
gous  pests  of  Colorado  are  mostly  those  that  work  below  ground. 
Bulletins  Numbers  70  and  91  by  F.  M.  Rolfs  describe  the  one  fun¬ 
gous  disease  that  causes  most  of  the  loss  to  potato  growers  of 
this  state.  This  disease  evidently  is  not  new  to  this  locality  for 
Boyd  in  his  History  of  Greeley  in  speaking  of  the  potato  industry 
during  the  Seventies  says :  “For  the  first  two  years  potatoes  did 
well  near  Greeley  on  this  side  of  the  river.  For  some  twelve  years 
none  could  be  raised  in  and  around  town.  They  did,  as  a  rule, 


1 .  Surface  Scab. 


PLATE  V.  SCAB  OF  POTATOES. 

2.  Deep  Scab.  3.  Apparent  Scab — work  of  the  Beetle. 


I. 


PLATE  VI.  HABITS  OF  GROWTH. 

Rural  N.  Y.,  No.  2.  2.  Improved  Peachblow.  3.  White  Pearl. 


The  Colorado  Potato  Industry.  17 

no  better  on  newly  broken  sod  than  on  old  sand.  Heavy  manuring 
of  the  land  did  not  help  the  matter.  The  vines  were  struck  with 
a  rust  or  blight.  This  fungus  made  the  leaves  thick  and  stiff, 
and  undoubtedly  destroyed  the  sap  and  prevented  the  leaves  from 
carrying  on  their  function.” 

This  is  a  good  superficial  description  of  the  effects  of  this 
fungus  as  it  looks  in  the  field.  From  its  past  history  ll  is  evi¬ 
dent  that  meteorological  conditions  have  a  strong  influence  on  the 
behavior  of  this  fungus.  Probably  there  has  been  no  year  since 
the  growing  of  potatoes  began  in  this  State  that  the  disease  has 
not  been  present,  but  much  of  the  time,  at  least  in  the  more  fa¬ 
vored  locations,  its  attacks  have  been  so  light  that  it  did  not  at¬ 
tract  the  attention  of  the  growers.  A  high  temperature,  exces¬ 
sive  moisture,  alkali  and  a  compact  soil  are  all  conditions  that 
probably  favor  the  development  of  the  fungus.  It  has  been  gen¬ 
erally  supposed  that  this  disease  is  introduced  into  the  fields  with 
the  seed  potatoes  as  nearly  all  seed  tubers  have  more  or  less  of 
the  fungus  on  their  surfaces  in  the  form  of  scab  or  the  black  dirt¬ 
like  patches  of  the  sclerotia  stage  of  the  disease.  Experiments 
with  treating  the  seed  with  formalin  and  corrosive  sublimate  show, 
however,  that  the  disease  occurs  just  the  same  whether  the  seed 
is  infected  with  the  disease  or  clean.  This  fungus  is  not  confined 
to  the  potato  plant  alone.  In  fact  it  is  not  known  just  how  many 
plants  act  as  a  host  for  it.  Peas,  beans,  beets,  alfalfa  and  many 
weeds  are  known  to  be  subject  to  its  attacks.  The  curious  fact 
remains  that  though  the  fungus  works  on  alfalfa,  potatoes  fol¬ 
lowing  alfalfa  are  not  generally  as  badly  diseased  and  produce 
a  larger  crop  than  when  they  succeed  themselves. 

General  Appearance  and  Eeeects  oe  the  Fungous  on 
Potatoes.  To  the  ordinary  observer,  this  disease  does  not  be¬ 
come  noticeable  till  the  middle  or  latter  part  of  the  growing  sea¬ 
son.  If  the  plants  be  examined  carefully  at  any  time  from  the 
first  sprouting  of  the  seed  till  the  harvest,  some  of  them  will  be 
found  affected  with  the  fungous.  Plate  II  of  Bulletin  No.  92  of 
this  Station  shows  the  appearance  of  the  disease  in  the  first 
stages.  Not  infrequently  if  missing  hills  are  examined  at  the 
time  the  plants  are  breaking  through  the  ground  the  sprouts  will 
be  found  to  have  started,  but  the  stems  have  been  girdled  with  a 
brown  or  black  canker  that  stops  growth.  But  if  the  injury  is 
not  serious  enough  to  kill  the  plant  at  this  stage,  it  will  have  a 
sickly  yellow  appearance  and  die  soon  after  getting  through  the 
ground.  From  the  time  the  plants  first  come  up,  all  through  the 
season,  here  and  there  through  the  field,  will  be  found  what  the 
growers  call  “blighted  plants.”  The  leaves  are  thickened,  and 
with  the  White  Pearl  especially,  the  leaves  draw  up  close  to  the 


1 8  The  Colorado  Experiment  Station. 

stem  so  as  to  show  the  under  side  and  give  the  ends  of  the  vines 
a  rosette  appearance.  Microscopical  examination  of  the  foliage 
or  upper  stems  of  these  plants  shows  no  traces  of  disease.  If 
the  plant  be  pulled  from  the  ground,  the  stem  will  frequently  be 
found  scabby,  black,  or  rusty  with  the  center  of  the  stem  discolor¬ 
ed.  If  the  attack  is  unusually  severe  or  in  the  last  stages,  the 
whole  stem  may  be  entirely  decayed  below  the  surface  of  the 
ground.  In  other  cases  the  bark  of  the  stem  may  seem  fairly 
smooth  and  clean,  but  a  split  stem  will  show  a  discolored  center. 
In  this  case  the  disease  has  started  at  the  base  of  the  stem,  that  is, 
at  the  junction  of  the  stem  and  the  old  seed.  Sometimes  healthy 
looking  vines  will  have  rusty  canker  spots  on  the  stems  and  no 
apparent  injury  result.  It  appears  to  be  only  those  vines  that 
are  either  entirely  girdled  or  those  diseased  on  the  inside  that  are 
destroyed.  The  fatal  effect  on  the  plant  of  this  disease  comes 
from  the  hyphae  of  Rhizoctonia  crowding  into  the  cells  of  the 
stem  and  stopping  the  circulation  by  clogging.  In  cases  where 
the  disease  works  only  on  the  outside  of  the  stem,  large  vines 
with  no  potatoes  are  frequently  produced  or  sometimes  little  po¬ 
tatoes  are  formed  at  the  axils  of  the  leaves  all  along  the  stems. 
The  past  season  has  been  unusually  favorable  for  the  development 
of  the  disease.  The  loss  from  it  in  this  state  was  probably  not 
less  than  two  and  a  half  or  three  million  bushels.  The  writer 
found  here  and  there  diseased  plants  in  all  fields  visited  during 
the  early  part  of  the  growing  season.  Diseased  plants  gradually 
became  more  numerous,  as  the  season  advanced,  but  were  not 
numerous  enough  to  be  considered  a  menace  till  the  latter  part  of 
July,  and  the  first  of  August,  when  a  large  part  of  many  fields 
showed  the  disease.  By  the  last  of  August  growth  had  stopped 
in  nearly  all  the  fields  and  hardly  a  plant  could  be  found  that  was 
not  more  or  less  diseased.  Great  variation  in  yield  resulted. 
Fields  of  Pearls  that  developed  early,  yielded  one  hundred  and 
fifty  or  more  sacks  per  acre  while  other  near  by  fields,  particularly 
Rurals,  did  not  exceed  thirty  sacks  per  acre.  The  question  of 
yield  this  year  seemed  to  be  simply  a  matter  of  how  far  the  tubers 
were  developd  when  the  growth  was  stopped  by  the  fungus. 

Experiments  in  the  laboratory  have  proven,  that  at  least  a 
large  part  of  the  so  called  scab  of  potatoes  in  this  state  is  a  direct 
result  of  the  action  of  this  fungus.  Sometimes  it  attacks  the 
tubers  causing  a  greater  or  less  degree  of  scab  without  causing  any 
apparent  injury  to  the  vines.  Again  both  the  vines  and  tubers 
are  affected  and  frequently  the  vines  are  destroyed  and  no  scab 
will  appear.  Some  localities  are  so  subject  to  the  disease  that 
potatoes  can  seldom  be  produced  at  all. 

Why  the  fungus  develops  these  peculiarities,  what  conditions 


The  Colorado  Potato  Industry. 


i9 


make  it  more  prevalent  in  some  localities  than  in  others,  and  what 
remedies  or  methods  of  culture  will  prevent  the  loss  from  this 
disease  are  problems  that  are  yet  to  be  solved. 

Treatment.  Some  experiments  were  made  with  treatment 
of  soils  with  copper  sulfate  at  the  rate  of  thirty-five  pounds  to 
the  acre  to  test  its  value  as  a  preventative  of  the  trouble.  No 
effect  either  way  could  be  detected.  Cultural  methods  em¬ 
ployed  by  different  growers  have  also  been  carefully  noted  but 
with  no  definite  results,  other  than  that  all  the  fields  that  pro¬ 
duced  satisfactory  yields  were  given  deep  cultivation,  while  the 
small  plots,  as  those  planted  in  gardens  even  in  the  most  success¬ 
ful  potato  growing  districts,  that  were  cultivated  with  one  horse  or 
kept  clean  with  a  hoe,  produced  nothing.  Many  fields  that  re¬ 
ceived  deep  cultivation  were  also  failures. 

SUGGESTIONS  TO  THE  GROWERS 

Although  the  potato  industry  of  Colorado  is  new  and  only 
partly  developed,  the  reputation  of  the  product  for  high  and  uni¬ 
form  quality  is  known  in  all  the  markets  of  the  country.  Few 
places  have  the  natural  advantages  for  producing  the  high  grade 
product  that  the  irrigated  potato  sections  of  Colorado  possess. 
Because  of  the  high  altitude  the  season  is  comparatively  short 
without  extremes  of  heat.  The  nights  are  cool.  The  amount  of 
moisture  can  for  the  most  part  be  controlled  and  the  soils  are  deep 
and  rich.  All  these  conditions  give  the  grower  an  opportunity 
to  produce  in  the  potato  the  same  standard  of  excellence  that  is 
maintained  by  the  fruit  growers  of  the  West. 

We  are  not  prepared  to  recommend  many  changes  in  the  me¬ 
thods  of  culture  practiced  in  the  potato  growing  sections  of  this 
State,  as  those  already  in  use  are  the  results  of  a  number  of  years 
experience  in  the  application  of  scientific  principles  of  soil  manage¬ 
ment  to  a  system  of  farming  that  is  hardly  known  in  the  East. 
Undoubtedly  the  greatest  need  among  the  potato  growers  is  or¬ 
ganization.  This  is  particularly  true  of  the  Greeley  District.  The 
compactness  of  the  district,  value  of  the  property  and  large  out¬ 
put  of  the  crop,  are  factors  that  might  make  a  growers  organi¬ 
zation  there,  a  success,  where  in  a  more  scattered  or  less  wealthy 
community,  good  results  would  be  less  easily  obtained.  It  is  not 
our  purpose  in  this  report  to  suggest  or  recommend  any  scheme 
of  organization.  The  advantages  to  be  gained  are  many.  At 
present  there  is  no  uniform  system  of  grading.  Scabby  or  mis¬ 
shapen  potatoes  may  be  put  on  the  markets  with  the  best  grades. 
There  is  nothing  to  hinder  potatoes  from  any  place  being  sold  as 
Greeley  potatoes.  With  a  registered  trade  mark  and  a  uniform 
system  of  grading  this  could  be  prevented  and  the  association 


20 


The  Coeorado  Experiment  Station. 


label  on  each  sack  would  be  a  guarantee  of  quality,  as  is  that  of 
the  various  fruit  growers  associations  in  the  West.  Comparative¬ 
ly  few  consumers  have  any  knowledge  of  varieties  in  potatoes. 
The  people  who  buy  Greeley  potatoes  and  get  a  certain  color  and 
quality  expect  to  get  the  same  thing  at  the  next  purchase.  If 
many  varieties  are  grown  and  all  go  under  one  name  disappoint¬ 
ment  is  sure  to  follow  and  the  reputation  of  the  product  is  injured. 
Only  a  few  varieties  are  now  grown.  One  or  two  of  these  do 
better  than  any  of  the  others  so  there  is  little  reason  for  growing 
any  but  these  standard  varieties  for  the  general  market. 

SEED  TREAMENT 

Results  from  the  use  of  formalin  or  corrosive  sublimate  treat¬ 
ments  have  not  been  such  that  we  can  recommend  their  use.  Both 
substances  have  caused  more  or  less  trouble  from  retarding  the 
germination  of  the  seed  and  in  some  cases  the  seed  has  been 
killed  by  their  use.  In  these  cases  it  is  probable  that  the  material 
was  used  too  strong  or  the  seed  was  left  in  the  solution  too  long. 
Granting  that  the  use  of  these  materials  will  clean  the  seed  of 
infection  of  the  scab,  the  treatment  is  practically  worthless  so  long 
as  the  soils  are  contaminated  with  the  fungus.  The  so-called 
“greening”  of  the  seed  potatoes  as  practiced  by  some  growers  in 
the  Greeley  District  is  undoubtedly  beneficial. 

The  treatment  of  cut  seed  should  receive  more  attention  than  it 
ordinarily  does.  It  is  a  well  known  fact  that  cut  seed,  allowed 
to  stand  for  any  considerable  length  of  time,  shrivels  badly  and  the 
buds  become  weakened.  Treating  the  fresh  cut  seed  with  air 
slaked  lime,  land  plaster  or  sulphur  tends  to  form  a  crust  over  the 
cut  surface  so  as  to  prevent  drying  to  some  extent  and  they  also 
tend  to  prevent  the  action  of  various  fungi,  worms  and  insects. 
These  materials  have  not  been  experimented  with  sufficiently  to 
know  which  of  them  is  the  best,  but  so  far,  observations  of  re¬ 
sults  have  led  us  to  favor  the  use  of  the  flowers  of  sulphur  as  being 
more  repellant  to  disease  than  the  other  two. 

POTATO  MACHINERY 

The  subject  of  machinery  is  one  of  general  interest.  All 
machines  do  fairly  good  work  but  none  have  been  perfected.  Near¬ 
ly  all  the  machines  used  in  the  state  are  made  in  the  eastern  states 
and  are  adapted  to  the  conditions  there.  Some  of  the  later  mo¬ 
dels  of  planters  are  improvements  on  the  older  styles  but  none 
of  them  get  a  perfect  stand  of  plants.  Much  depends  upon  the 
depth  that  it  is  desired  to  plant,  and  the  depth  of  planting  depends 
somewhat  on  the  variety  to  be  planted.  Varieties  differ  consider- 


The  Colorado  Potato  Industry. 


21 


ably  in  their  habit  of  growth.  Tubers  are  borne  on  root  stocks 
or  under  ground  stems  that  always  grow  from  the  stem  of  the 
plant  above  the  old  seed  tuber.  Figures  3,  1  and  2,  Plate  VI,  show  the 
characteristic  habit  of  growth  of  Pearl,  Rural  N.  Y.  No.  2  and 
Improved  Peachblow.  The  Pearl  sends  out  short  root  stocks  just 
above  the  old  seed  so  that  the  tubers  are  formed  closely  around  the 
center  of  the  hill  and  at  about  the  depth  that  the  seed  is  planted. 
Rural  N.  Y.  No.  2  has  a  longer  rootstock  and  is  apt  to  start  high¬ 
er  above  the  old  seed  so  that  the  tubers  are  more  scattered  in  the 
hill.  Some  of  them  are  deep  in  the  soil  and  others  will  be  close 
to  or  at  the  surface  of  the  ground.  The  Improved  Peachblow  is 
still  more  irregular  in  its  habit  of  tuber  growth.  These  peculiar 
habits  of  growth  make  less  difference  under  the  hilling  system  of 
culture  employed  in  the  irrigated  districts  than  where  the  level 
system  is  practiced. 

With  most  machines  the  seed  is  planted  too  shallow  rather 
than  too  deep.  Many  potatoes  that  are  supposed  to  be  planted 
four  or  five  inches  deep  are  really  not  more  than  one  or  two  in¬ 
ches  under  the  level  surface  of  the  soil.  If  the  soil  is  sufficiently 
moist  this  does  no  harm  but  if  the  soil  is  dry  at  the  surface,  a  poor 
stand  is  apt  to  result. 

ROTATION  OF  CROPS  AND  RHIZOCTONIA 

The  rotation  of  crops  as  practiced  in  this  state  does  not  tend 
to  lessen  the  amount  of  disease.  The  Rhizoctonia  which  causes 
the  blight  and  a  greater  part  of  the  scab  of  potatoes  works  on  al¬ 
falfa  as  well  as  potatoes.  So  far  as  is  known  the  disease  does  not 
live  on  the  cereals  so  that  is  has  been  suggested  that  if  potatoes 
could  be  preceeded  by  wheat  or  oats,  instead  of  alfalfa,  the  amount 
of  the  disease  might  be  lessened.  The  efficiency  of  a  rotation  of 
this  kind  is  doubtful,  however,  as  it  is  probable  that  the  disease 
lives  in  the  soil  more  than  one  year  without  any  host  plant,  more¬ 
over  the  loss  of  the  beneficial  effects  of  alfalfa  upon  the  soil  would 
possibly  be  more  than  the  ordinary  loss  from  the  disease. 

SELECTION 

A  large  part  of  the  improvement  in  plants  has  been  brought 
about  through  selection.  This  applies  to  plants  propagated  by 
vegetative  parts  as  well  as  those  propagated  by  seed.  All  the  do¬ 
mesticated  species  are  originated  either  from  crossing  or  varia¬ 
tions  and  are  fixed  in  their  particular  characteristics  by  selection. 
The  different  varieties  of  a  species  may  be  called  the  variations  of 
that  species.  When  a  variety  is  planted  year  after  year  it  is  sure 


22 


The  Colorado  Experiment  Station. 


to  revert  or  change  its  characteristics  (that  is  run  out)  if  selection 
of  seed  is  not  practiced.  This  is  particularly  true  of  a  species 
that  has  such  a  great  number  of  varieties  as  the  potato.  Varie¬ 
ties  in  this  way  are  frequently  subdivided  into  types.  In  a  small 
way  this  may  be  seen  in  any  potato  field.  A  good  example  may 
be  found  in  the  Improved  Peachblow.  Some  hills  will  be  found 
that  have  from  one  to  three  large  tubers  with  possibly  a  few  very 
small  ones.  The  large  ones  are  apt  to  be  cracked  so  as  to  be  un¬ 
salable.  Other  hills  may  have  one  large  tuber  with  several  others 
grading  down  to  the  very  small  specimens.  Now  and  then  will 
be  found  a  hill  with  from  eight  to  a  dozen  medium  sized  perfect 
shaped  tubers.  Every  man  has  in  his  mind  an  ideal  type  of  the 
variety  that  he  grows. 

HOW  TO  SELECT  SEED  POTATOES 

When  digging,  hills  will  be  found,  all  the  tubers  of  which  will 
conform  to  this  ideal.  If  these  tubers  be  saved  and  planted,  a 
large  part  though  not  all  of  them  ought  to  produce  potatoes  like 
the  seed.  These  should  be  selected  again  by  hills  and  all  should 
be  discarded  except  potatoes  from  those  hills  which  approximate 
the  ideal  type. 

The  longer  this  selection  is  carried  on,  the  greater  should  be 
the  proportion  of  tubers  like  the  original  selected  type. 

The  usual  objection  to  this  selection,  in  practice,  is  that  at 
digging  time  when  the  work  must  be  done,  the  grower  is  too  busy 
getting  in  the  crop  to  take  time  for  improvement  of  future  crops. 
The  selecting  can  be  done,  however,  without  taking  a  great  deal  of 
time.  When  the  digger  is  running,  one  man  should  follow  with 
a  basket  and  select  the  most  desirable  specimens  of  tubers  from  hills 
that  conform  to  his  ideal  type  of  that  variety.  Ordinarily  the  ma¬ 
chine  will  leave  the  tubers  in  such  shape  that  the  individual  hills 
can  be  separated.  In  this  work  do  not  look  for  perfect  tubers 
only.  Select  perfect  tubers  from  hills  in  which  all  of  the  tubers  are 
of  good  shape  and  of  sufficient  number  to  give  a  good  yield  even 
though  some  of  them  are  too  small  for  market. 

With  this  system  of  selection  enough  seed  potatoes  ought  to 
be  secured  in  one  day  to  plant  at  least  one  acre  of  land.  These  po¬ 
tatoes  should  be  sacked,  labeled  and  put  in  a  cool  place  by  themselves. 
The  following  spring  they  should  be  planted  at  one  side  of  the 
field  where  they  can  be  staked  off  from  the  rest  of  the  crop.  Most 
growers  prefer  to  plant  potatoes,  that  are  intended  for  seed,  late. 
A  very  rich  soil  is  not  desirable  for  growing  seed  potatoes  be¬ 
cause  of  the  tendency  to  produce  overgrown  tubers.  This  may 
be  overcome  to  some  extent  by  planting  more  seed  to  the  hill  or 
planting  the  hills  closer  together.  When  digging  time  comes  the 


The  Colorado  Potato  Industry. 


23 


same  process  of  selection  and  elimination  should  be  gone  through 
again.  In  this  way  the  improvement  of  type  and  yield  may  go  on 
from  year  to  year. 

Many  growers  prefer  green  or  immature  seed  to  that  which 
is  fully  developed.  Experiments  along  th'S  line  with  plants  pro¬ 
duced  from  seed  rather  than  by  vegetative  parts  have  shown  that  im¬ 
mature  seed  tend  to  produce  an  early  maturing  plant  and  also  one 
that  tends  to  produce  more  fruit  to  the  amount  of  plant  tissue  but 
at  the  expense  of  vitality  and  size  of  plant. 

This  law  does  not  necessarily  hold  good  with  the  potato  since 
the  repi  oduction  is  accomplished  by  means  of  the  vegetative  portion 
of  the  plant.  Experiments  along  this  line  with  the  potato  have  not 
been  carried  far  enough  to  give  definite  results. 

COST  OF  GROWING 

The  cost  per  acre  of  growing  potatoes  varies  to  a  consider¬ 
able  extent  according  to  the  soil,  season  and  price  of  labor.  One 
year  with  another  an  average  of  the  different  farms  would  not  be 
far  from  the  foil  wing  figures  which  are  taken  from  a  pamphlet  is 
sued  by  the  Greeley  Commercial  Club. 


Plowing  land - f _  $2.50 

Leveling  and  harrowing _  |  QQ 

Seed  Potatoes _ _ _  5  00 

Planting -  1 .50 

Cultivating _  2.50 

Irrigating - -  J  .50 

Digging -  750 

Sacks - 7.50 

Marketing -  6,00 


$35.00 


This  estimate  is  based  on  what  is  considered  a  good  yield  or 
from  200  to  300  bushels  per  acre.  The  first  six  items  are  prac¬ 
tically  uniform,  whatever  the  yield  may  be,  while  the  last  three 
depend  upon  the  yield  per  acre,  so  that  a  poor  yield  or  a  failure, 
reduces  the  cost  per  acre  by  about  one  half  and  an  extremely  large 
yield  increases  it  accordingly. 

The  price  of  Colorado  potatoes  has  a  wide  range  from  year 
to  year,  but  the  average  price  for  the  past  ten  years  has  been  65c 
per  hundred  lbs. 


1 


Bulletin  1  1 8 


January,  1907 


The  Agricultural  Experiment  Station 

OF  THE 


Colorado  Agricultural  College 


Western  Slope  Fruit  Investigation 

1906 

REPORT 

Field  Horticulturist 


By 

O.  B.  WHIPPLE 


The  Agricultural  Experiment  Station 

FORT  COLLINS,  COLORADO 


THE  STATE  BOARD  OF  AGRICULTURE 


Hon.  P.  P.  SHARP,  President , 
Hon.  HARLAN  THOMAS,  - 
Hon.  JAMES  L.  CHATFIELD, 
Hon.  B.  U.  DYE, 

Hon.  B  F.  ROCKAFELLOW, 
Hon.  EUGENE  H.  GRUBB 
Hon.  R.  W.  CORWIN  - 
Hon.  A.  A.  EDWARDS, 


Denver. 

Term 

Expires 

1907 

Denver. 

1907 

-  Gypsum. 

1909 

Rocky  Ford. 

1909 

Canon  City. 

1911 

Carbondale 

1911 

Pueblo. 

1913 

Fort  Collins. 

1913 

Governor  HENRY  A.  BUCHTEL,  \  _ 

President  BARTON  O.  AYLESWORTH,  \  ex'°^lcl° 


Executive  committee  in  charge. 

P.  F.  SHARP,  Chairman. 

B.  F.  ROCKAFELLOW.  A.  A.  EDWARDS. 


STATION  STAFF 


L.  G.  CARPENTER,  M.  S.,  Director  -  Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S.,  -------  -  Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D.,  -  -  -  -  -  -  -  Chemist 

WENDELL  PADDOCK,  M.  S. , . Horticulturist 

W.  L.  CARLYLE,  M.  S., . Agriculturist 

G.  H.  GLOVER,  M.  S.,  D.  V.  M.,  -  -  -  -  -  -  Veterinarian 

W.  H.  OLIN,  M.  S.,  -  ...  -  -  -  Agronomist 

H.  M.  COTTRELL,  M.  S.,  -  -  -  -  -  -  Animal  Husbandman 

R.  E.  TRIMBLE,  B.  S.,  ...  -  Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S.,  ------  -  Assistant  Chemist 

EARL  DOUGLASS,  M.  S.,  ------  Assistant  Chemist 

S.  ARTHUR  JOHNSON,  M.  S.,  -  -  -  -  Assistant  Entomologist 

B.  O.  LONGYEAR,  B.  S.,  -  -  -  -  Assistant  Horticulturist 

E.  B.  HOUSE,  M.  S.,  -  -  -  -  -  Assistant  Irrigation  Engineer 

F.  KNORR, . -  Assistant  Agronomist 

P.  K.  BLINN,  B.  S.,  -  -  Field  Agent,  Arkansas  Valley,  Rockyford 

E.  R.  BENNETT,  B.  S.,  -  -  -  -  -  Potato  Investigations 


Western  Slope  Fruit  Investigations,  Grand  Junction. 

O.  B.  WHIPPLE,  B.  S., . Field  Horticulturist 

E.  P.  TAYLOR,  B.  S.,  -------  Field  Entomologist 


OFFICERS 

President  BARTON  O.  AYLESWORTH.  A.  M.,  LL.  D. 


L.  G.  CARPENTER,  M.  S.,  -  -  -  -  -  -  -  -  Director 

A.  M.  HAWLEY, . .  Secretary 

MARGARET  MURRAY,  -  -  . Clerk 


The  Western  Slope  Fruit  Investigation. 


INTRODUCTORY. 


,  R  d®  ^  V0n  °f  frult  growers  of  Mesa  county  appeared  before  the 
^griculture  in  December,  1905,  and  requested  help  from  the 
xperiment  Station  in  questions  troublesome  to  fruit  growers  of  that  vic¬ 
inity  especially  along  the  line  of  plant  diseases,  insect  pests,  and,  subse¬ 
quently,  damage  from  seepage. 


.■Associate(^  Fruit  Growers  of  Mesa  county  felt  the  need  of  the 
wx>rk  sufficiently  to  pledge  $1,500  toward  the  cost  of  such  investigation. 
The  conditions  surrounding  the  Experiment  Station  did  not  permit  its  funds 
to  be  used  for  that  purpose.  Realizing  the  immediate  need,  the  State  Board 
ot  Agriculture  decided  to  appropriate  money  from  other  funds  to  carry  on 
the  mvesLgatmn  for  the  year  1906,  until  the  meeting  of  the  Legislature, 
with  the  expectation  that  the  Legislature  would  enable  the  work  to  be  con¬ 
tinued. 


„  mvestigation  in  a  general  way  was  to  include  two  men,  a  Field 

orticulturist,  and  a  Field  Entomologist,  with  headquarters  in  Grand 
Junction,  and  subsequently  seepage  investigations  were  undertaken.  The 
Field  Horticulturist  worked  under  plans  prepared  by  Professor  Paddock 
and  reported  directly  to  him;  the  Entomologist  worked  in  connection  with 
the  Field  Horticulturist  and  also  worked  under  the  plans  prepared  by 
Prof.  C.  P.  Gillette.  The  seepage  investigations  were  under  the  direction  of 
Professor  Carpenter,  and  were  carried  on  by  Prof.  E.  B  House  and  Mr 
F.  L.  Payne. 


Under  the  instructions,  every  orchard  in  Mesa  county  was  to  be 
visited  as  soon  as  possible,  and  inspected,  particular  attention  being  given 
to  spraying,  pear  blight,  crown  gall,  woolly  aphis  and  all  orchard  pests, 
cultivation,  drainage  and  irrigation,  and  in  fact,  all  orchard  operations  and 
an  orchard  survey  was  to  be  conducted  at  the  same  time,  and  an  endeavor 
to  get  the  history  of  each  orchard  as  far  as  possible.  In  this  way,  it  is 
possible  to  find  the  causes  contributing  to  successes  and  failures,  and  to 
decide  what  practices  have  proven  most  successful.  Blanks  were  prepared 
for  the  study. 


In  the  seepage  investigation,  a  detailed  study  was  to  be  made  of 
the  location  of  the  seeped  lands,  and  an  attempt  to  determine  the  cause,  in 
order  to  be  able  to  prescribe  a  remedy.  While  it  was  expected  that  sev¬ 
eral  years  would  be  required,  the  scope  of  the  work  expanded,  and  with 
the  development  arising  from  experience,  a  smaller  part  was  completed 
than  expected. 

The  Field  Horticulturist  at  Grand  Junction  is  Mr.  O.  B.  Whipple, 
who  was  transferred  from  Assistant  Horticulturist  at  Fort  Collins  to  take 
charge  of  the  work.  The  Field  Entomologist  is  Mr.  E.  P.  Taylor,  a  grad¬ 
uate  of  the  State  Agricultural  College  of  Fort  Collins,  and  formerly  As¬ 
sistant  State  Entomologist  of  Illinois,  and  in  the  seepage  investigations 
Prof.  E.  B.  House,  ,of  the  Experiment  Station  staff,  and  Mr.  F.  L.  Payne  of 
Wichita,  Kansas,  who  had  before  assisted  in  conducting  similar  investigations. 

This  is  a  report  of  the  Field  Horticulturist  to  the  Director  for  1906. 
It  was  not  originally  intended  for  publication,  but  it  is  believed  it  will  be 
useful,  and  therefore  is  issued  as  a  bulletin.  The  other  related  reports 
are  in  preparation. 

It  is  desirable  that  the  work  should  be  carried  on  for  a  series  of 
years  and  should  extend  as  soon  as  possible  to  other  fruit  growing  dis¬ 
tricts,  as  desired  by  Professor  Paddock  and  the  fruit  growers  of  the  West¬ 
ern  Slope,  and  this  continuation  depends  upon  funds  available  for  the  pur¬ 
pose. 

L.  G.  CARPENTER,  Director. 


Report  of  the  Field  Horticulturist  for  1  906. 

O.  B.  WHIPPLE. 


My  time  as  field  horticulturist  has  been  largely  devoted  to 
the  study  of  orchard  conditions  in  Mesa  county.'  During  the 
season  I  have  made  two  trips  to  Delta  county  to  investigate  the 
conditions  there.  I  find  it  nearly  impossible  to  divide  my  time 
to  any  great  extent  with  other  counties.  After  more  experience 
in  field  work  under  these  conditions  the  work  can,  no  doubt, 
be  carried  on  over  a  larger  territory.  Very  little  experimental 
work  has  been  undertaken  during  the  past  season  as  it  seemed 
best  to  follow  conditions  in  the  field  one  season  that  we  might 
take  up  experimental  work  more  intelligently  the  ensuing  year. 

In  my  work  I  have  given  special  attention  to  plant  diseases, 
cultivation,  watering,  pruning  and  the  collection  of  data  on  the 
fruit  industry. 

The  interest  taken  in  the  work  by  the  growers  has  been  very 
gratifying,  and  at  no  time  have  we  experienced  any  difficulty  in 
securing  the  co-operation  of  careful  growers  in  carrying  on  ex¬ 
periments.  The  success  of  our  work  depends  to  a  large  extent 
upon  this  friendly  co-operation  of  the  fruit  growers.  Our  cor¬ 
respondence  with  growers  has  not  been  all  we  desired  but  will 
no  doubt  increase  as  we  become  better  acquainted  and  the  plan  of 
our  work  better  known.  Requests  for  information  have  been 
numerous  but  on  account  of  the  limited  time  spent  in  the  office, 
some  growers  have  no  doubt  become  discouraged  in  trying  to 
reach  us  by  telephone.  I  have  tried  to  spend  as  many  evenings 
as  possible  in  the  office  where  I  hope  the  growers  will  learn  to 
find  me. 

The  orchard  survey  work  has  not  progressed  as  rapidly  as 
we  at  first  hoped  it  would  on  account  of  the  time  required  for 
other  investigations.  This  survey  has  been  carried  on  in  con¬ 
nection  with  other  work  as  far  as  possible.  This  part  of  the  in¬ 
vestigations  can  no  doubt  be  pushed  more  rapidly  during  the  re¬ 
mainder  of  the  year,  and,  while  the  summer  season  is  the  ideal 
time  for  this  work,  I  think  the  object  of  the  survey  can  be  accom¬ 
plished  during  the  winter  season. 

PLANT  DISEASES. 

Observations  on  plant  diseases  have  been  very  interesting 
and  some  important  conclusions  have  been  reached. 


6 


The  Colorado  Experiment  Station. 


ALTERNARIA. 

Experiments  were  undertaken  during  the  season  to  determine 
the  best  method  of  controlling  this  rot  which  was  thought  to  be 
damaging*  the  fruit  and  foliage  of  Keiffer  pear  and  Ben 
Davis  and  Gano  apples.  Three  orchards  were  selected  where 
severe  injury  was  reported  during  the  summer  of  1905  and  ex¬ 
periments  outlined.  Inquiries  among  orchard  men  led  me  to  be¬ 
lieve  that  a  part  of  this  injury,  at  least,  might  be  due  to  spray¬ 
ing,  and  the  experiments  were  planned  with  this  point  in  mind. 
In  one  orchard  a  block  of  seventy-five  Keiffer  pear  trees  was  se¬ 
lected  and  divided  into  blocks  I,  II  and  III.  Block  I  was  sprayed 
with  Bordeaux  mixture  (3-4-50)  on  April  14th.  The  buds  were 
well  started  at  this  time  and  were  out  far  enough  to  expose  the  in¬ 
dividual  blossom  stems.  This  block  was  again  sprayed  on  May 
8th  with  Bordeaux  mixture  (2-4-50),  with  3  lbs.  of  arsenate  of 
lead  added  to  each  fifty  gallons  of  Bordeaux  for  the  first  codling 
moth  spray. 

Block  II  was  sprayed  on  May  5th  and  8th  with  Bordeaux 
applied  at  the  same  strength  and  with  the  same  insecticide  as  used 
in  block  I,  and  was  again  spraved  with  the  same  material  on  lune 
8th. 

Block  III  was  sprayed  with  arsenate  of  lead  only,  during  the 
entire  season.  O11  July  10th  block  II  was  divided,  and  half  was  spray¬ 
ed  with  arsenite  of  lime  while  the  remainder  and  all  other  blocks 
were  sprayed  with  arsenate  of  lead.  A  light  rain  followed  and 
black  blotches  on  the  fruit  were  quite  noticeable  by  the  first  of  Au¬ 
gust.  All  other  blocks  sprayed  with  arsenate  of  lead  during  the  en¬ 
tire  season  were  perfectly  clean.  This  indicates  that  the  injury  in 
the  part  of  block  II  sprayed  with  arsenite  of  lime  was  due  to  burn¬ 
ing. 

In  the  second  orchard  a  block  of  fifty  Keiffer  pears  and  a 
block  of  fifty  Gano  and  Ben  Davis  apples  were  selected  for  experi¬ 
ments.  The  block  of  Keiffer  pears  was  divided  into  two  blocks 
and  block  I  was  sprayed  on  May  8th,  or  just  after  the  blossoms 
had  fallen,  with  Bordeaux  mixture  (2-4-50)  with  two  and  one 
half  pounds  of  arsenate  of  lead  added  to  each  fifty  gallons  of  Bor¬ 
deaux.  The  brand  of  arsenate  of  lead  used  was  of  poor  manu¬ 
facture,  and  on  May  23rd  the  check  trees  making  up  block  II  and 
sprayed  on  May  12th  with  arsenate  of  lead  only,  were  found  to  be 
badly  burned, while  the  foliage  and  fruit  of  block  I  showed  no  injury. 
The  injury  on  block  II  was  mostly  to  foliage  though  some  fruits 
were  burned,  most  of  which  dropped  early.  Block  I  was  saved 
by  the  excess  of  lime  in  the  Bordeaux  which  combined  with  the 
free  arsenic  in  the  lead.  A  good  grade  of  lead  was  used  on  all 
blocks  after  this  spraying. 

Block  I  was  again  sprayed  on  June  9th  with  Bordeaux  mix- 


Fruit  Investigation,  1906.  7 

ture  and  arsenate  of  lead.  No  further  signs  of  burning  or  Alter- 
naria  rot  appeared  on  either  block  during  the  remainder  of  the 
season. 

The  fifty  Ben  Davis  and  Gano  apples  were  sprayed  with  Bor¬ 
deaux  on  the  same  dates  as  the  pears,  leaving  the  remainder  of  the  or¬ 
chard  as  a  check.  The  owner  being  anxious  to  get  the  first  cod¬ 
ling  moth  spray  on  at  the  proper  time,  applied  it  five  days  earlier. 
Both  blocks  were  injured  severely  by  this  first  spraying  with  lead. 
Most  of  the  injured  fruits  dropped  early  and  at  picking  time  no 
injury  from  burning  or  Alternaria  was  noticeable  on  the  fruit  of 
either  check  or  sprayed  trees.  On  the  shaded  portions  of  large 
trees  sprayed  with  Bordeaux  a  slight  russeting  of  the  fruit  was 
noticed  but  not  serious  enough  to  cause  damage. 

The  experiments  in  the  third  orchard  were  practically  the 
same,  only  on  a  smaller  scale.  A  good  grade  of  arsenate  of  lead 
was  used  and  no  injury  from  burning  or  Alternaria  rot  was  found 
at  picking  time. 

With  these  experiments,  and  after  observations  in  many 
other  orchards  the  following  conclusions  were  reached : 

First;  that  Alternaria  is  in  most  cases  a  secondary  factor  in  causing 
the  decay  of  fruit. 

Second;  that  it  does  not  seem  to  be  able  to  gain  entrance  to  the  fruit 
through  healthy  tissue,  unless  it  be  in  cases  where  it  enters  the  core  cavity 
through  the  calyx  tube,  but  may  follow  any  injury,  as  spray  burn,  bruises  or 
worm  holes.  During  the  season  it  has  been  found  under  these  conditions, 
as  well  as  on  blighted  fruit  spurs  of  the  pear  and  in  the  germ  cavity  of 
peaches  with  split  pits. 

Third;  that  Keiffer  pears  cannot  be  sprayed  with  any  degree  of  safety 
with  other  than  a  standard  make  of  arsenate  of  lead.  The  nearer  mature  the 
fruit,  the  more  liable  it  is  to  injury,  and  if  possible,  no  sprays  should  be 
applied  later  than  July  10th.  With  thorough  spi'aying  early  in  the  season, - 
applications  later  than  this  date  are  unnecessary. 

Fourth;  that  if  Gano  and  Ben  Davis  apples  are  to  be  sprayed  with 
arsenite  of  lime,  special  care  should  be  given  to  its  preparation  and  a  good 
clear  day  selected  during  which  to  apply  it. 

•PEAR  BLIGHT. 

Pear  blight  has  been  severe  on  many  varieties  of  pears  this 
season  and  many  neglected  orchards  are  practically  gone.  Where 
reasonable  care  is  given  to  cutting  out  affected  limbs,  most  var¬ 
ieties  are  doing  well.  By  very  careful  cutting,  many  growers  are 
proving  that  pear  culture  is  still  profitable.  A  great  deal  may  be 
accomplished,  I  believe,  in  selecting  varieties.  Comparisons  made 
during  the  season  of  pear  orchards  seeded  to  grass  with  those  under 
cultivation  seem  to  show  little  difference  in  the  amount  of  blight. 

The  Flemish  Beauty,  Clapp  Favorite  and  Idaho,  fortunately 
three  worthless  varieties  from  a  commercial  standpoint,  should 
.  never  be  planted,  as  they  blight  badly.  Not  only  this,  but  trees 
of  these  varieties  should  be  taken  out.  While  it  is  possible  that 
these  Varieties  may  be  worked  over  to  other  varieties  to  advan- 


8 


The  Colorado  Experiment  Station. 


tage,  it  seems  very  probable  from  observations  of  the  season  that 
sooner  or  later  blight  will  get  into  the  trunk  and  kill  the  tree. 
So  often  does  this  seem  to  be  true  in  the  case  of  the  Idaho  that  it 
would  seem  advisable  to  discourage  the  working  over  of  this  var¬ 
iety.  Some  of  the  commercial  varieties  which  seem  to  be  most 
free  from  blight  are  Keiffer,  Anjou,  Mt.  Vernon,  Garber,  Howell 
and  Seckel.  Ee  Conte,  Sugar,  Bose  and  Sudduth,  four  varieties 
not  so  well  known,  seem  to  be  quite  free  from  blight.  Unfortun¬ 
ately  when  once  attacked,  Bartlett  seems  to  suffer  quite  severely. 
Winter  Nelis  is  fairly  resistant,  while  Clairgeau  seems  to  suff  er 
severely  from  attacks  in  the  trunk  and  larger  branches.  Persis¬ 
tent  cutting  out,  I  think,  will  do  much  to  save  the  pear  orchards. 
If  it  does  not  pay  to  cut  out  the  blight,  it  does  not  pay  to  grow 
pears  and  owners  of  badly  infested  orchards  should  pull  them  out. 
Many  growers  pronounce  their  pear  orchards  the  most  profitable 
piece  of  land  on  the  ranch,  but  these  are  men  who  cut  out 
the  blight.  The  general  practice  with  these  men  is  to  cut  out  blight 
at  least  three  times  during  the  summer. 

Blossom  and  twig  blight  in  the  apple  seems  to  be  on  the  in¬ 
crease  and  has  attracted  a  great  deal  of  attention  the  past  sea¬ 
son.  It  has  not  only  caused  a  loss  of  crop,  but  a  great  deal  of 
anxiety  in  regard  to  the  future  of  the  trees  attacked.  However, 
the  only  loss  seems  to  be  in  the  destruction  of  the  crop  before  it 
has  set,  and  the  killing  of  whole  fruit  spurs  carrying  blighted  blos¬ 
soms.  Only  in  a  few  sweet  apples  and  in  very  severe  cases  has 
the  blight  done  any  damage  to  larger  limbs.  The  general  tendency 
seems  to  be  for  the  blight  to  kill  the  spur  back  to  the  branch 
from  which  it  springs  and  then  die  out.  In  especially  bad  cases 
in  Tolman  Sweet  we  have  found  branches  of  one  and  two  year 
old  wood  killed.  Even  where  the  fruit  spur  is  hardly  more  than 
a  bud,  it  seems  to  be  an  exception  for  blight  to  do  any  damage  to 
the  branch  from  which  it  springs. 

There  seems  to  be  some  difference  in  varieties  as  to  their  re¬ 
sistance  to  blossom  blight.  All  the  sweet  apples  blight  badly. 
The  Ralls,  Dr.  Walker,  Wealthy,  Pewaukee  and  Jonathan  are  also 
subject  to  severe  attacks.  No  varieties  seem  to  be  immune  in 
badly  infected  orchards,  but  the  Winesap,  Gano  and  Ben  Davis  are 
as  resistant  as  any.  However  it  seems  hardly  possible  to  give 
definite  lists,  for  there  are  exceptions,  and  the  tables  are  often  turned. 

“Twig  blight' '  is  also  bad  in  some  varieties,  as  the  sweet 
apples,  Jonathan,  Pewaukee,  Red  Romanite,  Willow  Twig  and 
Transcendent  Crab.  In  this  case  the  blight  rarely  affects  more 
than  the  current  season’s  growth.  Badly  blighted  pear  trees 
neglected  by  the  owner  of  the  orchard  or  a  nearby  neighbor  were 
often  found  to  be  the  original  source  of  infection  in  these  badly 
blighted  orchards.  With  more  careful  cutting  out  of  pear  blight, 


Fruit  Investigation,  1906.  9 

I  think  the  blossom  and  twig  blight  in  apples  would  tend  to  de¬ 
crease.  Some  growers  have  trimmed  out  all  blighted  spurs  and, 
while  it  improves  the  looks  of  the  tree  enough  to  pay  for  the  trouble, 
I  hardly  think  leaving  these  spurs  would  increase  the  liability  to 
attack  the  following  year,  as  by  mid-summer  all  blighted  spurs 
are  thoroughly  dried  and  it  would  seem  impossible  for  any  hold¬ 
over  blight  to  exist  in  them.  I  believe  pear  trees  are,  in  the  ma¬ 
jority  of  cases,  responsible  for  carrying  the  blight  through  to  the 
next  blossoming  season. 


PEACH  MILDEW. 

Probably  owing  to  the  unusual  amount  of  rain  during  the 
early  part  of  the  season,  peach  mildew  has  been  of  more  impor¬ 
tance  than  usual.  Losses  from  those  of  small  per  cents  to  those 
of  total  crops  have  been  reported.  Measures  used  in  com¬ 
batting  this  disease  should  be  of  a  preventative  nature  rather 
than  as  a  cure.  After  the  fungus  has  once  obtained  a 
good  foothold  on  the  fruit,  nothing  can  be  done  to  save  the  peach. 
The  fungus  may  be  killed,  but  the  flesh  underneath  refuses  to 
grow  and  at  ripening  time  we  have  a  one  sided  peach  or  a  peach 
with  a  sunken  spot  on  it.  The  disease  is  capable  of  destroying 
a  crop  in  a  short  time  and  prompt  action  is  important. 

Observations  made  in  orchards  where  the  attack  was  severe 
show  that  one  thorough  spraying  with  half-strength  Bordeaux  (2- 
4-50)  will  destroy  the  mildew.  Thorough  winter  spraying  of  in¬ 
fested  orchards  with  'full  strength  Bordeaux  should  prove  a  very 
important  safe-guard.  The  first  appearance  of  the  disease  in 
early  summer  should  be  followed  by  prompt  action  on  the  part  of 
the  owner,  and  the  orchard  thoroughly  sprayed  with  half  strength 
Bordeaux.  A  week’s  delay  in  some  orchards  often  means  a  loss 
of  fifty  per  cent  of  the  crop  and  two  weeks  a  total  loss. 


GUMMOSIS. 

Cases  of  Gummosis  in  peach  trees  have  been  found  occasion¬ 
ally.  Gum  starts  to  flow  from  the  trunk  or  larger  branches  dur¬ 
ing  the  early  part  of  the  summer  and  large  drops  are  formed  on 
the  bark,  often  reaching  an  inch  in  diameter  and  are  nearly  as 
round  as  marbles.  In  severe  cases  the  tree  dies  in  the  latter  part 
of  the  season.  While  the  number  of  cases  reported  need  cause 
no  alarm,  the  loss  of  a  single  tree  in  an  orchard  does  not  add  to 
its  value,  and  with  reasonable  care,  I  think  the  loss  might  be  avoided. 


IO 


The  Colorado  Experiment  Station. 


While  no  large  number  of  trees  have  been  treated,  experiments 
seem  to  show  that  a  vertical  slitting  of  the  bark  about  the  affected 
trunk  or  branch  during  the  early  stages  will  save  the  tree.  Use  a 
sharp  knife  for  this  work  and  do  not  be  afraid  of  cutting  too  deep. 
Make  the  cuts  about  two  inches  apart.  While  I  do  not  pronounce 
this  a  sure  cure  in  all  cases,  it  seems  worthy  of  a  trial  on  trees  in  the 
first  stages.  When  the  drops  of  gum  reach  the  size  of  marbles, 
the  tissues  are  broken  down  to  such  an  extent  that  no  practical 
method  of  treatment  would  save  the  tree. 


ROOT  ROTS. 


Two  apparently  distinct  forms  of  root  rot  are  found.  One 
form,  which  is  proving  the  least  destructive  of  the  two, 
seems  to  show  no  preference  for  varieties,  and  confines  it¬ 
self  to  that  part  of  the  tree  below  the  ground.  The  other 
seems  to  work  exclusively  on  the  Ben  Davis  and  Gano. 
and  the  trunk  as  well  as  the  roots  are  affected.  The  disease 
often  extends  upward  into  the  large  branches.  The  first  indication  of 
the  disease  is  the  appearance  on  the  trunk  of  spots  of  a  chocolate 
color.  When  peeled  off  the  bark  has  a  peculiar  marbled  appearance, 
the  diseased  portions  standing  out  in  sharp  contrast  to  the  healthy 
tissue.  The  disease  soon  kills  the  bark  and  it  dries  down  to  the 
wood,  taking  on  a  dark  brown  color.  Two  seasons  are  required  for 
the  disease  to  kill  the  tree.  The  first  season  the  trunk  is  girdled  and 
the  foliage  drops  early.  This  early  ripening  of  the  foliage  is 
often  the  most  prominent  symptom,  and  diseased  trees  can  be 
easily  picked  out  in  the  early  fall.  Trees  showing  an  early  bronzing 
of  the  foliage  are  generally  found  girdled  by  this  disease.  The  sec¬ 
ond  season  the  tree  starts  into  leaf  as  the  normal  tree,  generally  set¬ 
ting  fruit,  and  dies  in  mid-summer,  the  fruit  and  leaves  clinMne*. 
I  he  disease  seems  to  be  infectious,  as  the  trees  appear  in  groups,  and 
in  many  cases  it  appears  as  though  it  were  carried  by  water.  When 
a  diseased  tree  is  found,  several  more  are  generally  found  in 
the  same  row.  However,  other  varieties  besides  the  Ben  Davis 
and  Gano  may  stand  in  the  same  row  with  diseased  trees  on  either 
side  and  show  no  sign  of  contracting  the  disease.  The  fact  that 
Ben  Davis  and  Gano  are  very  tender  as  regards  the  application 
of  arsenical  sprays  has  suggested  to  my  mind  that  the  trouble  may 
be  due  to  arsenic  collecting  about  the  crown  of  the  tree  and  kill¬ 
ing  the  bark.  However,  the  fact  that  trees  sprayed  with  arsenate 
of  lead  and  arsenite  of  lime  are  alike  affected,  seems  to  be  contrary 
to  such  a  hypothesis. 


Fruit  Investigation,  1906. 


1 1 

/ 

Prompt  removal  of  the  trees  affected  seems  at  present  to  be 
the  only  treatment  that  can  be  suggested.  Reports  indicate  that 
the  disease  has  only  been  in  the  orchards  two  or  three  years  at  the 
most.  Soil  conditions  seem  to  have  no  relation  to  the  disease,  as  it 
is  found  on  all  kinds  of  soils. 

CROWN  GALL. 

Only  a  few  cases  of  crown  gall  have  come  to  my  observation 
in  Mesa  county,  a  few  trees  having  been  killed  by  it.  A  disease 
which  appears  very  much  the  same  and  no  doubt  the  same  disease 
that  is  called  crown  gall  by  other  stations,  seems  to  be  doing  con¬ 
siderable  injury  to  the  Vinifera  vineyards  of  this  section.  Rose 
of  Peru  seems  to  suffer  most  severely.  Muscat,  Tokay  and  Corn- 
ichon  have  been  found  affected,  however.  When  the  disease  at¬ 
tacks  the  crown  of  the  plant,  death  seems  to  follow  in  one  or  two 
years.  When  the  canes  are  affected,  growth  seldom  starts  from 
above  the  gall,  but  new  growth  starts  from  below  and  the  plant 
keeps  alive,  but  bears  very  poor  crops.  While  it  is  probably 
transmitted  from  plant  to  plant  in  the  vineyard,  this  is  uncertain, 
but  observations  in  the  vineyards  seem  to  bear  out  the  statement. 

I  think  it  would  be  well  to  remove  diseased  vines  and  give 
closer  inspection  to  nursery  stock.  Under  the  present  system, 
grapes  are  passed  without  inspection. 


PHYSIOLOGICAL  TROUBLES. 

Many  yellow  pear  trees  are  found  in  the  valley.  Observations 
seem  to  indicate  poor  soil  conditions,  probably  due  in  most  cases  to 
excessive  watering.  The  foliage  takes  on  a  yellow  cast,  and  in  the 
last  stages  the  leaves  become  thickly  sprinkled  with  small  deadened 
spots  and  fall  from  the  tree.  The  trees  grow  more  enfeebled  from 
year  to  year  and  are  finally  pulled  out. 


SMALL  PEACHES. 

Many  growers  claimed  that  their  peaches  did  not  attain  the 
customary  size  while  they  were  very  sure  that  they  had  thinned  as 
carefully  as  in  previous  years.  There  is  no  doubt  some  truth  in 
the  assertion  and  also  a  cause.  The  peach  trees  were  severely 
frozen  in  most  localities  during  the  winter  of  1904-05.  Not  only 
were  the  peach  buds  killed,  but  the  wood  was  damaged  to  quite  a 
serious  extent.  Many  of  these  trees  were  not  pruned  as  heavily 
as  they  should  have  been  following  such  a  freeze,  and  did  not  make 


12 


The  Colorado  Experiment  Station. 


a  good  recovery.  The  winter  of  1905-06  was  less  severe  and  the 
fruit  buds  passed  the  winter  safely.  While  the  growers  thinned 
their  peaches  as  carefully  as  usual,  the  trees,  having  failed  to  fully 
recover  from  the  severe  freeze  in  one  growing  season,  were  un¬ 
able  to  mature  the  normal  crop.  Where  severely  pruned,  the 
trees  matured  their  crop  well.  Following  severe  freezes  which 
injure  the  wood,  it  would  be  well  to  thin  the  first  crop  more  closely. 


COPPER  SULPHATE  INJURY. 

Copper  sulphate  has  been  placed  about  trees  with  injurious 
results  by  some  orchard  men.  When  taken  up  by  the  roots  the 
material  blasts  the  foliage  and  causes  it  to  fall.  The  most  tell¬ 
tale  effect  is  a  blackening  of  the  outer  ring  of  the  sap  wood  and 
cambium.  When  taken  up  by  the  roots  in  a  concentrated  form,  the 
wood  and  bark  near  the  base  of  the  tree  are  killed  in  strips  of 
varying  width.  Nearer  the  top  where  the  material  spreads  more, 
the  tendency  is  for  the  leaves  to  drop,  and  later  a  new  growth  starts. 
The  upper  limbs  probably  recover.  The  strips  of  bark  on  the  trunk 
and  limbs,  however,  seem  to  be  perfectly  dead. 

The  stock  solution  used  in  spraying  with  arsenite  of  lime, 
prepared  b}^  dissolving  white  arsenic  in  water  and  sal  soda,  is  very 
destructive  to  plant  life.  The  general  practice  of  keeping  this 
solution  in  the  orchard  under  a  tree  should  be  discouraged.  If  a 
small  amount  is  spilled,  or  if  the  vessel  leaks,  the  material  will 
soon  kill  the  tree.  In  fact,  it  almost  appears  as  though  in  some  cases 
the  material  will  kill  peach  trees  when  placed  under  them  in  an  open 
vessel.  The  fumes  given  off  when  boiling  this  solution  will  kill 
trees  without  a  doubt,  and  this  boiling  should  be  done  some  distance 
from  the  orchard.  I  have  seen  trees  standing  twenty  feet  from  an 
open  packing  house  door  killed  on  the  side  next  to  the  packing 
house  in  which  the  material  was  boiled. 

Some  Ben  Davis  and  Gano  orchards  have  shown  a  very 
sickly  yellow  color  during  the  summer,  and  investigations  have 
shown  that  the  trees  were  suffering  from  arsenical  poisoning.  The 
trees  were  sprayed  with  arsenite  of  lime  in  which  the  quantity  of 
lime  used  was  deficient,  or  with  an  arsenate  of  lead  which  contain¬ 
ed  a  large  amount  of  free  arsenic.  The  growth  of  foliage  is  scant 
and  the  color  yellow.  Though  the  material  may  have  been  used 
only  once,  the  effect  seemed  to  last  through  the  season.  There 
seems  no  reason  to  believe  but  that  the  trees  will  recover  the  coming 
season. 

THINNING  APPLES. 

Experiments  were  undertaken  in  thinning  apples  during  the 
eaily  part  of  the  season.  An  orchard  was  selected  in  which  large 


Fruit  Investigation,  1906. 


•13 


blocks  of  Jonathan  and  Winesap  were  carrying  a  very  heavy  load. 
The  thinning  was-  done  in  the  early  part  of  July.  The  apples 
were  actually  counted  on  some  trees  and  a  definite  number 
left.  Assuming  that  from  150  to  160  apples  of  these  varie¬ 
ties  make  a  box  of  fancy  apples,  the  trees  were  thinned 
to  produce  from  six  to  twelve  boxes.  The  trees  were  eleven 
years  old  and  the  best  results  on  the  Jonathan  seemed  to 
come  from  trees  yielding  eight  boxes,  running  about  160  apples 
to  the  box.  Trees  bearing  more  than  this,  run  smaller  in  size  and 
less  uniform.  The  Winesap  gave  better  results  when  thinned  to 
about  six  or  seven  boxes.  Trees  of  Jonathan  thinned  to  eight 
boxes  would  yield  95  per  cent  or  over  fancy  fruits  as  far  as  size 
and  color  were  concerned.  Unthinned  trees  which  packed  about 
sixteen  boxes  gave  50  per  cent  of  small  fancy  fruit,  but  on  the  days 
the  thinned  trees  were  stripped  not  50  per  cent  could  be  picked  from 
the  unthinned  trees  on  account  of  poor  color.  At  least  25  per  cent 
did  not  reach  a  good  color.  Thinned  trees  which  picked  twelve 
boxes  required  two  pickings  and  run  on  an  average  about  90  per 
cent  fancy.  These  trees  averaged  about  fifteen  feet  in  height  and 
had  a  twenty  foot  spread. 

Observations  will  be  made  next  season  on  the  thinned  and  un¬ 
thinned  trees  to  determine  the  effect  of  thinning  on  the  ensuing 
year’s  crop.  The  rule  followed  was  to  leave  only  one  fruit  on  a 
spur  and  remove  those  from  the  tips  of  limbs.  Observations  on  un¬ 
thinned  trees  showed  that  apples  on  the  tips  of  limbs  seldom  reach 
a  good  size. 


GRAPE  GROWING. 

The  associations  and  growers  have  complained  of  poor  results 
in  shipping  grapes.  The  trouble  seemed  to  be  that  they  molded 
before  they  got  to  market.  Correspondence  was  taken  up  with 
California  growers  and  observations  carried  on  in  the  vineyards 
during  the  season. 

From  California  rules,  and  from  my  own  observations,  I  be¬ 
lieve  the  growers  use  more  water  than  is  necessary.  In  one  case, 
I  actually  found  the  bunches  shriveling  from  excessive  watering. 

The  reason  some  varieties  do  not  ship  well  is  no  doubt  because 
they  are  not  ripe  enough.  The  short  season  does  not  give  them 
time  to  thoroughly  mature.  The  California  people  say  a  grape 
must  be  ripe  to  ship  well.  Another  point,  I  believe,  is  carelessness 
in  packing,  in  not  cutting  out  injured  berries  nor  allowing  the  stems 
to  wilt.  Grapes  packed  tight  while  the  stems  are  stiff  crack  easily 
and  this  gives  entrance  to  mold.  Owing  to  the  method  of  pruning 
practiced  to  allow  of  easy  covering,  many  of  the  bunches  come  in 
contact  with  the  ground  and  should  be  thoroughly  dried  before 
packing.  Experiments  have  been  taken  up  to  determine  a  more 


r4  The  Colorado  Experiment  Station. 

satisfactory  method  of  pruning-  which  will  hold  the  grapes  off  the 
giound  and  still  allow  of  the  vines  being-  easily  covered.  The  gen¬ 
eral  tendency  seems  to  be  to  prune  too  short,  and  light  crops  of 
inferior  bunches  are  the  result.  No  varieties  should  be  pruned 
shorter  than  four  eyes,  and  the  Muscat,  Sweetwater,  Sultana,  Em¬ 
peror  and  Thompson.  Seedless  should  be  pruned  to  eight. 
Some  system  of  training  must  be  found  which  will  hold  the  fruit 
oft  the  ground.  More  care  should  be  given  to  watering.  Three 
waterings,  I  believe,  are  enough.  Dry  soil  conditions  should  pre¬ 
vail  during  the  ripening  period. 

As  to  varieties,  the  Flame  Tokay  and  Cornichon  seem  best 
adapted  to  the  Palisade  region  where  early  frosts  do  not  strike. 
For  the  rest  of  this  district,  Muscat,  Rose  of  Peru,  Tinfadel  and 
Chasselas  Victoria  must  be  used,  blame  Tokay  may  succeed  on 
early  soil  where  the  soil  conditions  can  be  well  controlled.  Thomp¬ 
son  Seedless,  Sultana  and  Sweetwater  do  well,  but  do  not  sell. 

Grape  mildew  (Uncinula  spiralis)  has  caused  some  loss  in 
vineyards,  and  experiments  have  been  started  this  fall  to  determine 
the  best  method  of  controlling  it.  One  block  was  given  a  fall  treat¬ 
ment  of  Bordeaux  before  covering,  and  other  blocks  will  be  sprayed 
the  coming  season  and  various  fungicides  tested. 

Expei  iments  wei  e  undertaken  to  show  the  value  of  sacking 
Vimfeia  giapes  to  piotect  them  from  rots  and  mildew  and  to  im¬ 
prove  their  appearance.  The  cost  of  sacking  was  found  to  be 
about  one-half  cent  pei  pound  for  most  varieties,  while  those  pro¬ 
ducing  larger  bunches  can  no  doubt  be  sacked  at  one-half  this  cost. 
The  earlier  varieties  seemed  to  fare  very  well  in  sacks,  unless  they 
were  subject  to  cracking,  as  some  of  the  more  tender  skinned  var¬ 
ieties  aie.  Bunches  in  sacks  laying  on  the  ground  split  and  molded 
badly.  Foi  the  late  vaiieties  sacking  proved  to  be  a  failure  as  it 
retarded  the  coloring  and  ripening  and  seemed  to  give  no  protec¬ 
tion  from  frost.  The  stems  were  frozen  the  first  frosty  night  and 
the  bunches  wilted  and  failed  to  ripen.  The  Muscat  and  Thomp¬ 
son  s  Seedless  did  veiy  well  sacked  and  their  appearance  was  much 
improved. 

SETTING  YOUNG  TREES. 

I  1  actically  all  the  systems  of  laying  out  orchards  and  plant¬ 
ing  young  trees  are  used  in  the  fruit  sections  of  western  Colo¬ 
rado.  The  distance  of  setting  varies  from  i6’xi6’  to  3o’x32’  for 
apples  and  from  I2’xi2’  to  2o’x2o’  for  peaches,  but  the  experienced 
growers  are  giving  the  greater  distance. 

The  practice  of  setting  Missouri  Pippin,  as  fillers,  in  with  the 
standard  varieties  of  apples  is  quite  common.  In  the  peach  districts 
peaches  are  often  used  for  the  same  purpose.  I  hardly  think  the  prac¬ 
tice  is  to  be  encouraged,  as  the  average  grower  will  not  take  them  out 


Fruit  Investigation,  1906. 


15 


before  they  crowd.  The  tendency  is  to  leave  them  in  until  the 
shape  of  the  other  trees  is  ruined. 

Trees  as  a  rule  are  not  handled  carefully  in  transplanting  and 
a  larger  per  cent  is  lost  than  is  necessary.  The  most  common 
method  of  setting  is  to  plow  a  furrow  and  with  a  little  additional 
digging,  set  the  titees  in  this.  For  the  first  watering,  the  water  is 
generally  run  through  this  furrow.  It  is  then  filled,  or  left  open  for 
other  waterings.  Many  leave  it  open  the  whole  season,  but  it  is 
generally  thought  best  to  fill  it  in  and  water  from  the  sides  before 
the  sun  gets  too  hot.  The  practice  of  leaving  this  furrow  open 
for  most  of  the  summer  seems  to  give  good  results,  but  there  is 
a  tendency,  I  believe,  to  set  too  deep.  I  think  it  a  very  good  me¬ 
thod  if  the  furrow  is  very  shallow.  The  most  common  method  of 
watering  is  to  fill  this  furrow  after  the  watering  at  planting  time, 
and  run  new  furrows  on  either  side  of  the  row  and  as  close  as 
possible.  This  system  will  give  excellent  results  if  the  man  who  is 
irrigating  sees  that  water  passes  all  the. trees  properly.  It  is  poss¬ 
ible  to  water  trees  too  often,  however,  and  the  man  who  is  inclined 
to  water  too  heavy  should  keep  his  ditches  at  some  distance  from 
the  trees.  With  a  scant  supply  of  water,  the  system  of  watering- 
in  the  original  furrow  in  which  the  trees  were  set  will  give  the 
best  results.  Young  orchards  are  either  cultivated,  or  planted  to 
secondary  crops.  The  most  common  secondary  crops  are  canta¬ 
loupes,  potatoes,  corn,  oats  and  white  beans.  Cantaloupes  do  well 
on  the  lighter  soils  but  other  crops  are  generally  sown  on  heavy 
soils.  Oats  is  a  poor  crop  for  the  young  orchard,  as  it  is  generally 
cut  just  in  time  to  force  the  grasshoppers  to  eat  leaves  and  bark 
from  the  trees  before  frost.  The  cutting  of  any  noticeable  growth  in 
the  orchard  at  mid-season  is  a  dangerous  practice  on  this  account. 
On  sandy  soils  cantaloupes  are  proving  a  favorite  crop.  The  fur¬ 
rows  for  watering  the  cantaloupes  should  be  as  far  from  the  tree 
rows  as  possible  that  late  watering  of  the  trees  may  be  avoided. 
This  is  very  important  in  young  peach  orchards.  Many  inexper¬ 
ienced  growers  water  their  peach  trees  too  late,  and  as  a  result, 
have  them  killed  back  during  the  winter. 

Young  trees  are  seldom  pruned  carefully  enough  after  the 
first  year,  and  long,  willowy  branches  which  bend  to  the  ground 
with  the  first  load  of  fruit  is  the  result.  Greater  distance  in  plant¬ 
ing  should  be  urged  and  more  care  in  regard  to  the  forming  of  the 
young  tree.  Too  many  second  class  trees  are  set,  the  growers 
failing  to  realize  that  a  poor  tree  is  dear  at  any  price. 

GENERAL  ORCHARD  CONDITIONS. 

It  is  a  general  practice  among  orchard  men  to  water  too  much 
and  neglect  cultivation,  and  often  the  soil  is  handled  very  poorly. 
A  large  per  cent  of  the  soil  is  rather  heavy  to  be  handled  well  under 


i6 


The  Colorado  Experiment  Station. 


irrigation,  and  with  the  method  of  watering  commonly  used,  it  is 
often  impossible  to,  touch  these  soils  with  the  cultivator  from  the 
first  watering  in  early  summer  until  the  following  spring. 

It  is  often  the  case  that  shallow  furrows  and  a  large  head  of 
water  are  used  and  the  result  is  a  flooding  of  the  whole  surface. 
When  dry  enough  to  work  again,  the  soil  has  run  together  and  the 
surface  is  so  hard  that  it  is  impossible  to  cultivate  it,  and  the  grower 
resorts  to  frequent  watering  to  keep  the  orchard  going.  In  these 
soils  the  water  settles  slowly  and  a  smaller  head  run  in  deeper 
ditches  would  no  doubt  prove  more  satisfactory. 

I  think  growers  with  these  heavy  adobe  soils  should  also  re¬ 
sort  to  the  planting  of  cover  crops  to  improve  soil  texture 
They  could  gradually  be  brought  into  shape  where  they 
could  be  more  easily  handled  after  irrigation.  Growers,  as  a  rule, 
pay  too  little  attention  to  the  sub-soil.  Too  often,  the  rule  follow¬ 
ed  is,  if  you  can  kick  up  dust  on  the  surface,  irrigate.  The  ap¬ 
pearance  of  the  tree  indicates  to  a  great  extent  its  needs,  but  after 
all,  it  is  an  examination  of  the  sub-soil  which,  most  surely  deter¬ 
mines  whether  the  orchard  needs  water  or  not. 

General  rules  which  it  might  be  well  for  growers  tc  follow  in 
applying  water  are  as  follows  : 

The  more  sandy  the  soil,  the  greater  the  number  of  ditches, 
the  shorter  the  run  in  both  time  and  distance. 

The  longer  the  ditches,  the  larger  the  head. 

The  stiffer  the  soil,  the  fewer  and  deeper  the  ditches,  the  long¬ 
er  the  run  in  time  and  distance,  and  the  smaller  the  head. 

PROBLEMS  FOR  THE  ENSUING  YEAR. 

Some  of  the  problems  for  the  coming  year  as  brought  out  by 
this  season’s  work  are  as  follows : 

Pear  Blight  and  its  control,  giving  especial  attention  to  tne 
form  known  as  blossom  blight  in  apples. 

Peach  mildew  and  the  effects  of  lime-sulfur  wash  as  a  winter 
spray  in  comparison  with  Bordeaux  mixture. 

Grape  mildew  (Uncinula  spiralis)  and  its  control  and  the  ef¬ 
fect  of  winter  and  summer  spraying. 

Observations  on  grape  growing  in  general  with  reference  to 
watering,  pruning,  packing  and  shipping. 

Further  study  of  the  root-rots  of  apples  to  determine,  if  pos¬ 
sible,  the  causes  and  remedies. 


February  1907 


v-*\ 

Bulletin  1  1 9 

The  Agricultural  Experiment  Station 

- OF  THE - 

Colorado  Agricultural  College 


Western  Slope  Fruit  Investigation 

1906 


Report  of 

The  Field  Entomologist 


- -BY - 

E.  P.  TAYLOR 

f 


PUBLISHED  BY  THE  EXPERIMENT 
FORT  COLLINS,  COLORADO 
1907 


STATION 


The  Agricultural  Experiment  Station. 


FORT  COLLINS,  COLORADO 


the  State  Board  of  agriculture 

Hon.  P.  F.  SHARP,  President . Denver 

Hon.  HARLAN  THOMAS . .  ..  .Denver. . 

Hon.  JAMES  L.  CHATFIELD . Gypsum..'.  ' 

Hon.  B.  U.  D1:E . Rocky  Ford. 

Hon.  B.  F.  ROCKAFELLOW . Canon  City 

Hon.  EUGENE  H.  GRUBB . . Carbondale” 

Hon.  A.  A.  EDWARDS . Fort  Collins 

Hon.  R.  W.  CORWIN . Pueblo . 

Governor  HENRY  A.  BUCHTEL,  ) 

President  BARTON  O.  AYLESWORTH, 


TERM 

EXPIRES 

....1907 
..  ..1907 
....1909 
....1909 
....1911 
....1911 
....1913 
....1913 


A.  M.  HAWLEY,  Secretary 


EDGAR  AVERY  Treasurer 


Executive  Committee  in  Charge 

P.  F.  SHARP,  Chairman. 


B.  F.  ROCKAFELLOW. 


A.  A.  EDWARDS 


STATION  STAFF 

L.  G.  CARPENTER,  M.  S.,  Director . Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S . Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D . Chemist 

WENDELL  PADDOCK,  M.  S . Horticulturist 

W.  L.  CARLYLE,  M.  S.  . . . Agriculturist 

G.  H.  GLOVER,  M.  S.,  D.V.  M . Veterinarian 

W.  H.  OLIN,  M.  S., . Agronomist 

R.  E.  TRIMBLE,  B.  S . Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S . Assistant  Chemist 

EARL  DOUGLASS,  M.  S . Assistant  Chemist 

S.  ARTHUR  JOHNSON,  M.  S . ..Assistant  Entomologist 

B.  O.  LONG1EAR,  B.  S .  Assistant  Horticulturist 

H.  M.  COTTRELL,  M.  S . Animal  Husbandman 

E.  B.  HOUSE,  M.  S  . Assistant  Irrigation  Engineer 

F.  KNORR .  . Assistant  Agronomist 

P.  K.  BLINN,  B.  S . Field  Agent,  Arkansas  Valley,  Rocky  Ford 

E.  R.  BENNE1T,  B.  S . Potato  Investigations 

Western  Slope  Fruit  Investigations,  Grand  Junction: 

O.  B.  WHIPPLE,  B.  S . Field  Horticulturist 

E.  P.  TAILOR,  B.  S . Field  Entomologist 


OFFICERS 


President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 


L.  G.  CARPENTER,  M.  S. 

A.  M.  HAWLEY . 

MARGARET  MURRAY... 


.  .Director 
Secretary 
. Clerk 


WESTERN  SLOPE  FRUIT  INVESTIGATION 

Report  of  Field  Entomologist* 

SEASON  OF  1998 

E.  P.  Taylor,  Grand  Junction,  Colorado 


The  principal  lines  of  work  for  the  season  have  been — 

( 1 )  Experiments  upon  practical  methods  of  controlling  the  prin¬ 

cipal  insect  pests  of  the  orchard. 

(2)  Collection  and  study  of  other  economic  insects. 

(3)  Visitation  of  orchards  by  request  or  otherwise. 

(4)  Attendance  at  fruit  growers’  association  meetings,  farm¬ 

ers’  institutes,  county  fairs,  horticultural  society  meet¬ 
ings,  etc.,  where  questions  relating  to  the  work  of  this 
office  were  being  considered. 

The  experiments  carried  on  with  injurious  insects  have  been 
in  cooperation  with  orchard  men  whose  loss  from  these  pests  has 
invited  tests  of  measures  of  control.  The  experiments  have  served 
as  practical  demonstrations  in  each  neighborhood  in  which  they  were 
carried  on,  and  have  served  as  object  lessons  at  the  same  time  they 
were  revealing  new  facets.  They  have  been  the  objects  of  the 
deepest  local  interest.  The  territory  covered  by  the  demonstra¬ 
tive  experiments  has  been  thus  far  limited  to  points  lying  in  the 
lower  Grand  Valley,  principally  in  the  orchard  sections  surrounding 
Grand  Junction,  Palisade,  and  Fruita. 

CODLING  MOTH.  ( Cydia  pomonella  Linn.) 

Introductory — The  codling  moth  has  received  the  greatest  share 
of  attention.  Spraying  experiments  have  been  completed  in  five 
orchards  of  the  locality  and  the  results  successfully  answer  the  prin¬ 
cipal  questions  relating  to  the  control  of  the  insect. 

Probably  no  district  in  the  United  States  is  better  equipped  with 
modern  spraying  apparatus  than  the  orchard  district  of  Grand  Valley. 
Nearly  $100,000  are  invested  in  spraying  apparatus  in  the  county  of 
Mesa  alone,  but  in  spite  of  this  fact,  codling  moth  ravages  have 
injured  the  fruit  to  the  extent  of  a  great  many  hundreds  of  thou¬ 
sands  of  dollars  annually  for  some  years  past,  and  in  spite  of  the 
fact  that  some  orchardists  have  applied  as  many  as  ten  or  more 
sprayings  per  season.  The  past  season  has  cost  the  growers,  by 
careful  estimate,  over  $36,000  for  material  used  in  making  up  their 

*This  bulletin  is  a  companion  to  Bulletin  118,  which  gives  the  report 
of  the  Field  Horticulturist  for  1906,  Western  Slope  Fruit  Investigation. 

The  general  plan  for  the  entomological  investigations  were  made  by 
Prof.  C.  P.  Gillette,  and  the  work  was  under  his  direction. 

The  work  was  rendered  possible  by  other  funds  than  the  government 
appropriations  for  the  Experiment  Station,  a  considerable  portien  from 
the  fruit  associations  of  Mesa  County,  and  the  remainder  from  the  State 
Board  of  Agriculture. 


4  COLORADO  EXPERIMENT  STATION. 

arsenical  sprays.  This  season’s  work  has  determined  these  failures 
to  be  due  to  several  causes:  (i)  lack  of  thoroughness  of  method;  (2) 
lack  of  proper  spraying  material,  and  (3)  lack  of  knowledge  of  the 
exact  life  history  of  the  moth. 

The  experiments  demonstrated  that  this  pest,  the  most  impor¬ 
tant  of  all  to  the  gruit  grower  of  Colorado,  may  be  cot?rolled  by 
arsenical  sprays  applied  properly  and  at  the  correct  time' 

The  number  of  sprays  required  to  control  the  moth  in  an  orchard 
will  depend  principally  upon  (1)  previous  infestation  of  orchard; 
(2)  proximity  to  other  infested  orchards;  (3)  efficiency  of  earlier 
sprays,  and  (4)  variety  of  fruit. 

To  obtain  results  of  greatest  practical  value  to  the  fruit  grower, 
orchard  blocks  of  considerable  size  were  chosen  and  given  treatment 
in  the  most  thoroughgoing  and  intelligent  manner.  Records  of  every 
detail  were  tabulated,  and  at  the  close  of  the  season,  in  determining 
results,  very  large  numbers  of  apples  were  given  hand-to-hand  inspec¬ 
tion.  For  example,  over  100,000  apples,  representing  upwards  of  600 
bushel  boxes,  were  given  a  prost  critical  examination  to  reveal,  as 
nearly  as  possible,  the  exact  outcome  of  the  experiment. 

Life  History  Studies — A  study  of  the  life  history  of  the  moth 
carried  through  the  season  showed  many  things  of  vital  importance 
relating  to  the  proper  time  to  spray.  No  great  variation  or  change 
of  habit  of  the  moth  was  noted.  The  time  required  for  the  passing 
of  each  stage  of  the  insect  was  practically  identical  with  other  obser¬ 
vations  of  the  insect  in  the  state.  The  time  or  dates  of  transfor¬ 
mations  of  the  moth  were  found,  however,  to  be  much  earlier  than 
for  the  majority  of  the  other  fruit  sections  of  Colorado,  and  some  varia¬ 
tion  exists  between  the  different  portions  of  the  Grand  Valley,  trans¬ 
formations  taking  place  earlier,  as  a  rule,  in  the  region  about  Palisade 
than  in  the  country  surrounding  Grand  Junction  or  Fruita. 

,  Parasites — Natural  parasites  of  the  insect  were  studied,  one  of 
the  most  interesting  being  the  minute  bee,  Tricho gramma  pretiosa, 
laying  its  eggs  and  developing  within  the  tiny  egg  of  the  codling  moth. 

Bands — The  use  of  bands  is  not  discouraged,  but  they  can  not 
be  depended  upon  alone  to  control  the  moth.  If  used,  the  old  ones 
which  have  remained  on  the  tree  through  the  winter  should  be 
cleaned  up  by  April  1st  to  prevent  larvae  from  changing  to  pupae 
and  moths  making  their  escape.  They  should  also  be  gone  over  at 
least  every  ten  days  through  the  summer  until  the  middle  or  latter 
part  of  August,  after  which  there  will  be  little  danger  of  moths  emerg¬ 
ing  until  the  following  spring. 

Spraying  Experiments — As  stated,  spraying  with  arsenicals  was 
the  standard  remedy  adopted,  and  the  studies  were  made  upon  (1) 
Time  to  spray;  (2)  Kind  of  spray,  and  (3)  Way  to  spray. 

Time  to  Spray — The  time  to  apply  the  first  spray  in  the  experi¬ 
ment  conducted  was  determined  by  the  condition  of  the  calyx  of  the 
bloom,  and  that  of  the  later  sprays  by  careful  and  systematic  obser¬ 
vation  for  the  appearance  of  the  eggs  of  the  moth. 

Close  observation  of  the  calyx  will  determine  when  it  is  in  an 


FIELD  ENTOMOLOGIST.  5 

ideal  condition  for  spraying.  This  time  should  be  following  the  drop¬ 
ping  of  the  petals  but  before  the  closing  of  the  calyx.  A  period  not 
to  exceed  from  five  to  seven  days  for  any  one  variety  would  cover 
the  time  when  this  first  spray  should  be  applied.  Sprayed  too  early 
or  before  the  petals  are  fallen,  bees  about  the  bloom  are  in  danger 
of  being  destroyed,  and,  sprayed  too  late,  the  green  sepals  will  have 
come  together  at  their  tips,  closing  the  calyx  cup  against  all  possi¬ 
bility  of  being  filled  with  the  poison. 

The  center  blossoms  are  invariably  the  first  to  open  their  petals 
and  first  to  drop  them.  They  are  first  to  close  their  calyces  and  most 
likely  to  set  fruit  which  will  remain  without  dropping  from  the  tree. 
It  is  therefore  evident  that  this  first  spraying  should  be  done  with 
these  blossoms  in  mind.  The  first  eggs  do  not  appear  for  several 
weeks  later.  When  the  young  larvae  hatch  from  these  eggs,  the  larger 
per  cent  of  them  enter  at  the  calyx,  and  if  the  first  spraying  has  left 
the  calyx  containing  a  liberal  amount  of  poison,  their  first  meal  will, 
in  all  probability,  be  their  last.  Sixty  per  cent  or  more  of  the  first 
generation  larvae,  according  to  this  summer’s  observations,  entered 
at  the  calyx.  For  the  remaining  forty  per  cent  or  less  entering  at 
the  side  or  stem  end  of  the  apple,  a  second  spray  must  be  applied 
early  enough  to  coat  the  surface  of  the  small  apple  with  poison  before 
the  hatching  larvae  make  their  appearance,  and  this  coating  must  be 
maintained  upon  the  fruit  until  the  first  generation’s  eggs  have 
hatched. 

Other  conditions  being  right,  two  sprayings  with  an  adhesive 
arsenical  will  perform  this  end,  and  the  first  generation  thus  prac¬ 
tically  destroyed.  There  being  but  two  full  generations  of  the  insect 
through  the  season,  if  the  first  be  destroyed  there  should  be  no  second 
left  with  which  to  contend. 

As  stated  above,  however,  in  common  practice  there  will  be  cases 
where  more  than  two  sprays  are  necessary,  and  these  additional  ones 
should  be  directed  against  the  second  generation. 

Any  one  may  determine  the  proper  time  to  spray  by  observations, 
upon  time  of  egg  appearance,  though  in  practice  this  is  more  or  less 
difficult  for  the  average  orchardist. 

The  date  of  appearance  of  the  blossoms  upon  fruit  trees  is  de¬ 
pendent  upon  meteorological  conditions  for  the  spring.  These  same 
conditions  regulate  the  initial  appearance  of  the  adult  moth,  and  as 
its  times  for  transformation  are  fairly  constant  thereafter,  it  seems 
possible  that  a  general  rule  may  be  made  for  common  use,  based 
upon  the  blooming  of  the  fruit  in  spring.  Such  a  general  rule  is 
herewith  presented,  thought  to  be  dependable,  at  least  in  the  general 
locality  wherein  it  was  determined,  and  if  conclusions  above  stated  are 
correct,  the  rule  should  apply  for  other  points  as  well.  Observations 
upon  the  time  of  appearance  of  the  insect  in  any  of  its  stages  could 
be  made  to  supplement  the  general  rule.  The  efficiency  of  the  first  two 
sprays  suggested  will  largely  determine  the  necessity  of  the  later 
sprays.  The  dates  given  are  those  applying  to  the  blooming  and 
spraying  of  Jonathans  at  Fruita  this  year,  and  should  be  considered 


6 


COLORADO  EXPERIMENT  STATION. 


as  subject  to  variation  with  place,  season,  and  variety.  The  egg  ob¬ 
servations  were  made  upon  trees  receiving  no  treatment  throughout 
the  season. 


HOW  TIME  TO  SPRAY  WAS  DETERMINED  IN  EXPERI¬ 
MENTAL  ORCHARD. 


Petals  dropped— calyces  open _ May  11 

First  spray _ May  11 

First  eggs  seen _ May  21 

Numbers  eggs  seen  _ ...June  1 

Second  spray _ June  2 

First  generation,  eggs  maximum _ June  13-19 

First  generation,  eggs  minimum _ June  28 

Second  generation,  eggs  begin _ July  2 

Third  spray— (suggested) _ July  2 

Second  generation,  eggs  abundant _ July  17 

Fourth  spray— (suggested) _ July  18 

Second  generation,  eggs  maximum _ July  25-31 

Fifth  spray— (suggested)  _ August  1 

Second  generation,  eggs  diminished  to 

about  - Sept.  1 


The  time  in  which  an  orchard  must  be  completed  with  the  first 
spraying  will  be  of  greater  importance  than  the  time  required  for 
second  or  other  later  sprays.  Power  spraying  outfits  make  it  possi¬ 
ble  to  cover  larger  orchards  in  less  time  than  with  hand  apparatus, 
but  it  has  been  found  that  under  ordinary  conditions  one  good  power 
outfit  should  not  be  expected  to  cover  more  than  twenty  acres  of  full¬ 
bearing  orchard  at  the  first  codling  moth  spray. 

In  apple  orchards  of  mixed  varieties  those  blooming  first  should 
be  sprayed  first.  Pears  do  not  close  their  calyces  as  quickly  as  apples, 
and  their  first  spraying  may  be  longer  delayed. 

Kind  of  Spray — The  experiments  of  the  year  demonstrated  that 
Swift’s  arsenate  of  lead  was  slightly  superior  to  the  arsenite  of  lime 
so  far  as  killing  effect  upon  worms  was  concerned.  The  difference 
seemed  to  be  less  than  4  per  cent,  but  though  the  cost  of  the  lead  is 
considerably  more,  it  is  probable  that  with  a  heavy  yield  of  fruit  of 
high  market  value  the  lead  would  probably  more  than  pay  for  the  dif- 
ference  in  cost.  It  is  more  convenient  and  less  liable  to  injure  foliage. 
Other  brands  of  arsenate  of  lead  were  used  with  nearly  equal  suc¬ 
cess  in  controlling  the  worms,  but  some  samples  had  been  improperly 
made  and  caused  injury  to  foliage  and  fruit  from  an  excess  of  free 
aisenic  contained.  Arsenite  of  lime,  used  with  sufficient  lime,  will 


TIME  TO  SPRAY— 
GENERAL  RULE. 


(1.)  Petals  off-caly¬ 
ces  open. 

(2.)  (a)  One  month 
from  full  bloom. 

( b )  Three  weeks 
from  center 
calyces  closing. 

(c)  When  apples 
are  about  t  in. 
diameter. 

(3)  One  month  from 

(2) 

(4)  Two  weeks  from 

(3) 

(5)  Two  weeks  from 

(4) 


FIELD  ENTOMOLOGIST. 


7 


cause  no  injury  to  trees  under  ordinary  conditions,  though  it  is  more 
liable  to  do  injury  than  properly  made  lead  arsenate.  Injury  to  trees 
from  arsenical  sprays  is  more  or  less  dependent  upon  variety  of  fruit 
and  meteorological  conditions  at  time  of  or  following  spraying.  A 
practice  among  some  orchard  men  the  past  season  in  Mesa  County  has 
been  to  use  arsenate  of  lead  for  the  first  and  second  sprays,  and  if  fur¬ 
ther  spraying  is  found  necessary  the  cheaper  arsenite  of  lime  is  sub¬ 
stituted. 

Arsenate  of  lead  was  used  at  the  rate  of  12  pounds  paste  per  200 
gallons  of  water  in  the  experimental  orchard. 

Arsenite  of  lime  was  used  at  the  rate  of  1  pound  arsenic,  4  pounds 
sal  soda,  30  pounds  lime  per  200  gallons  of  spray,  the  arsenic  and  sal 
soda  being  boiled  together  in  a  small  quantity  of  water  for  fifteen 
minutes  until  dissolved,  after  which  the  lime  slacked  with  water  to 
form  a  milk  was  added.  , 

,  Both  arsenate  of  lead  and  the  arsenite  of  lime  sprays,  from  their 
white  coating  upon  the  leaves,  produce  a  shading  effect,  which  in  our 
arid  climate  serves  a  secondary  beneficial  effect  by  reducing  transpi¬ 
ration  by  the  foliage. 

Method  or  Way  to  Spray — In  the  experiments  of  the  year  it  was 
shown  that  the  method  of  application  had  more  to  do  with  success 
than  a  difference  of  the  insecticides  used.  The  variation  between  poor 
spraying  and  very  good  spraying  might  well  vary  between  20  per 
cent  and  98  per  cent,  while,  as  shown,  the  two  insecticides  showed 
variation  of  only  about  4  per  cent. 

For  the  12-year-old  apple  trees  in  the  experiment  at  Fruita, 
an  average  of  12.9  gallons  of  spray  was  applied  per  tree  for  the  first 
spray,  and  9.9  gallons  were  used  for  later  ones. 

For  the  early  spraying  a  coarser  spray  of  liquid,  such  as  would 
be  given  by  a  Bordeaux  nozzle  or  a  coarse  Vermorel  nozzle  cap,  is 
desirable.  At  this  spraying  the  tree  should  be  drenched  with  a  strong, 
driving,  coarse  spray.  It  should  be  directed  straight  into  the  calyx 
cups  that  a  maximum  amount  of  poison  may  be  placed  in  position 
there.  It  was  determined  by  actual  count  that  at  spraying  time  aver¬ 
age  apple  trees  had  two-thirds  of  their  blossoms  pointing  in  an  up¬ 
ward  direction  and  one-third  in  a  downward  direction.  It  is,  then, 
apparent  that  spray  must  be  directed  downward  upon  the  tree  as  well 
as  upward  through  the  branches.  It  was  found  necessary  with  full¬ 
bearing  trees,  in  order  to  insure  thorough  work,  that  spraying  be 
directed  downward  from  the  top  of  a  tower  constructed  over  the  spray 
wagon.  Where  power  outfits  are  used,  and  where  the  rows  are  of 
such  a  distance  apart  that  the  inner  halves  of  any  two  can  be  treated 
from  a  point  midway,  it  will  be  found  that  on  medium  to  large  trees, 
two  men  upon  the  tower  and  one  man  spraying  upward  from  the 
ground  will  be  found  most  satisfactory.  Spray  poles  eight  to  twelve 
feet  long  should  be  used  by  both  ground  and  tower  men.  In  one  of 
.the  experimental  orchards  the  height  of  tower  man’s  reach  was  twenty- 
five  feet  above  the  ground. 


8 


COLORADO  EXPERIMENT  STATION. 


For  the  later  sprays,  a  nozzle  producing  a  fine  mist  is  desir¬ 
able.  A  nozzle  of  the  double-vermorel  type,  arranged  in  such  a  way 
that  the  direction  of  the  nozzle  can  be  placed  at  any  angle  with  the 
spray  pole,  is  wanted.  The  size  of  aperture  wanted  in  the  nozzle 
cap  will  depend  upon  the  pressure  maintained.  The  higher  pres¬ 
sures  can  be  directed  through  larger  apertures  and  still  produce  as 
fine  a  spray.  Higher  pressures  economize  upon  material  and  time, 
and  under  ordinary  conditions  are  most  desirable. 

In  the  experiment  conducted  upon  the  orchard  of  Mr.  G.  W. 
Marchant,  of  Fruita,  two  sprayings  with  Swift’s  arsenate  of  lead  (12 
pounds  per  200  gallons)  applied  at  the  times  indicated  in  the  above 
table,  and  in  a  thorough  manner,  produced  98  per  cent  winesap,  95.6 
Ben  Davis,  and  91.8  Jonathan  apples  free  at  picking  time  from  all 
worm  holes.  Picked,  unsprayed  Jonathans  in  a  block  in  the  same 
orchard  gave  only  43.1  per  cent  free  from  worm  holes,  and  49  per 
cent  of  the  apples,  by  actual  count,  originally  borne  by  the  trees,  had 
fallen  to  the  ground,  96  per  cent  wormy  before  picking.  Onlv  15 
per  cent  of  the  total  crop  of  sprayed  Jonathans  fell  to  the  ground  as 
windfalls,  and  74.1  of  these  were  perfect  apples.  The  apples  in  the 
sprayed  plats  were  treated  with  a  repetition  spray  following  a  heavy 
rain,  though  by  comparison  with  plats  left  untreated  with  such  spray 
it  was  found  that  the  additional  or  repetition  spray  was  unnecessary. 

The  complete  details  of  this  summer’s  experiments  and  obser¬ 
vations  upon  the  codling  moth  will  be  available  in  a  special  bulletin 
issued  by  the  Colorado  Agricultural  Experiment  Station,  which  bul¬ 
letin  is  now  under  preparation. 

HOWARD  SCALE.  ( Aspidiotus  howardi  Ckll.) 

This  pest  is  one  of  greatest  importance  to  the  pear  growers  of 
parts  of  Colorado.  Besides  the  pear,  it  is  known  to  infest  prune, 
plum,  apple,  almond,  and  certain  shade  and  forest  trees. 

The  life  history  of  the  insect  was  partially  worked  out  during  the 
year  and  experiments  conducted  showed  the  insect  to  be  possible  of 
cheap  and  complete  control  by  spring  applications  of  the  lime  and 
sulfur  wash. 

As  a  bulletin  is  also  soon  to  be  issued  upon  this  pest  and  its  rem¬ 
edies,  based  principally  upon  this  season’s  investigations,  details  of  the 
work  on  the  insect  may  be  ommitted  in  this  general  report. 

PEACH  TWIG-BORER.  ( Anarsia  lineatella  Zell.) 

Introductory — Experiments  conducted  at  Palisade  have  demon¬ 
strated  the  great  value  of  arsenate  of  lead  against  the  twig-borer  of 
the  peach,  which  caused  considerable  damage  to  the  peaches  in  this  and 
other  localities  of  Western  Colorado. 

Former  recommendations  for  the  control  of  this  insect  have  been 
for  spring  applications  of  lime  and  sulphur  washes.  This  has  in  fact, 
been  a  most  successful  treatment,  but  the  use  of  lead  arsenate  against 
the  twig-borer  of  the  peach  is  destined  to  meet  with  equal  popularity 
when  its  efficiency,  cost,  and  convenience  of  preparation  and  application 
are  considered. 


FIELD  ENTOMOLOGIST.  9 

The  peach  twig-borer  is  one  of  the  most  important  pests  to  the 
peach  growers  of  Western  Colorado.  All  of  the  peach  spraying  car¬ 
ried  on  in  the  Grand  Valley  the  past  spring  was  directed  against  either 
the  peach  aphis  or  the  peach  twig-borer. 

It  is  estimated  that  this  pest  cost  the  peach  growers  of  California 
over  a  million  dollars  in  the  four  years  following  1898.  To  the  grow¬ 
ers  of  Grand  Valley  it  has  cost  much  loss  for  some  years  past,  and  its 
distribution  on  the  Western  Slope  of  the  state  seems  to  be  quite  gen¬ 
eral  wherever  peaches  are  grown. 

Life  History  and  Injury — The  injury  is  caused  by  a  small  pinkish 
brown  worm,  with  black  head,  measuring,  when  fully  grown,  about 
one-half  inch  long.  The  worm  is  the  larval  or  immature  stage  of  a 
small  greyish  moth. 

The  winter  is  passed  by  the  larvae,  still  very  minute,  in  small 
chambers  hollowed  out  within  the  spongy  tissue  of  the  bark  at  the 
crotches  of  small  limbs.  The  chamber  is  lined  with  silk  of  the  larva’s 
secretion,  and  the  only  evidence  of  the  presence  of  the  chamber  is  in 
a  very  small  and  inconspicuous  heap  of  frass  or  peach-wood  dust 
standing  outward  from  the  mouth  of  the  burrow.  Early  in  the  spring, 
at  about  the  same  time  the  foliage  of  the  peach  show1?  as  small  green 
tufts  upon  the  twig  tips,  the  larvae  leave  their  burrows  and  attack 
the.  tender  twigs,  boring  into  them  near  their  tips  and  down  through 
their  pitch,  forming  galleries  from  one-third  to  one  and  one-half  inch 
in  length. 

Examinations  of  infested  peach  trees  at  Palisade  last  spring 
showed  these  bored  twigs  wilting  and.  turning  brown  early  in  the 
month  of  May.  Later  in  the  season,  twigs  bearing  half  a  dozen  leaf 
tufts  near  their  tips  would  have  each  bored  and  killed  and  from  all 
appearances  by  the  same  larvae.  This  injury  to  the  terminal  twigs 
constitute  an  important  injury  to  the  tree.  Young  peach  trees  are 
usually  worst  infested,  their  growth  being  sometimes  greatly  retarded. 

On  the  18th  of  May  a  number  of  larvae  were  taken  in  peach 
twigs  at  Palisade  and  kept  in  water  in  a  closed  cage  at  my  insectary. 
An  examination  of  the  cage  May  24  showed  that  two  of  the  larvae 
had  already  changed  to  brown  chrysalids  or  pupae,  both  emerging 
on  May  28. 

On  May  20  many  larvae  were  also  found  concealed  about  the 
base  of  the  tree  at  the  surface  of  the  earth  and  hiding  about  the 
bark,  and  it  seems  that  at  this  date  the  majority  of  the  larvae,  which 
hibernated  over  winter  in  the  small  bark  cavities,  have  now  completed 
their  feeding  on  the  twigs  and  are  descending  for  pupation.  As 
stated,  the  usual  habit  of  the  first  or  hibernating  brood  of  larvae  is  to 
burrow  into  the  twigs.  A  few  instances  were  "found,  however,  where 
small  peaches,  still  no  larger  than  a  pea,  were  burrowed  into,  leaving 
the  fruit  with  a  hollow  cavity  within. 

The  small  second  generation  worms  were  seen  beginning  their 
work  early  in  June.  It  is  this  generation  which  brings  about  another 
and  by  far  the  greater  amount  of  injury  to  the  peach  crop.  Larvae 
from  this  generation  make  their  way  directly  into  the  forming  peach 


10 


COLORADO  EXPERIMENT  STATION. 


itself,  and  the  “gummy”  peach  is  the  result.  Projecting  bits  or 
masses  of  exuded  gum  appear  on  the  surface,  and  from  their  appear¬ 
ance  and  impaired  keeping  qualities  they  are  rendered  unfit  for  mar¬ 
ket.  Some  peaches  containing  larvae  of  the  twig-borer  find  their 
way  into  boxes  to  be  marketed  on  account  of  having  the  borer  deep 
in  the  peach  or  within  the  pit  without  external  signs  of  habitation. 
Such  fruit,  however,  is  first  to  soften  and  decay,  and  should  be  ex¬ 
cluded,  if  possible. 

Control — At  Grand  Junction  last  spring  I  received  many  inquir¬ 
ies  from  peach  growers  as  to  the  best  measures  of  twig-borer  control. 

So  far  as  published  accounts  were  available,  contact  insecticides, 
such  as  kerosene  emulsion  or  lime  and  sulfur  wash,  were  the  ones 
considered  most  effective.  The  previous  spring  Mr.  Frank  Berger, 
of  Palisade,  and  a  few  other  growers  of  that  place,  had  used  arse¬ 
nate  of  lead  as  a  spring  spraying,  instead  of  the  lime  and  sulfur 
wash  ordinarily  used,  and  reported  no  injury  from  twig-borer  follow¬ 
ing.  As  none  of  these  orchards  had  portions  left  with  no  spray,  I 
could  not  determine  for  certainty  whether  the  favorable  results  re¬ 
ported  by  these  orchardists  was  due  to  the  effectiveness  of  the  spray 
or  to  the  lack  of  original  infestation  by  the  twig-borer. 

To  determine  this  it  seemed  necessary  to  prove  the  value  of  the 
arsenical  spray  by  an  experiment  carried  on  in  an  orchard  where  a 
considrable  portion  was  left  untreated,  which  was  done  in  the  five- 
year-old  peach  orchard  of  ninety-two  trees  belonging  to  Mr.  S.  L. 
Carson,  at  Palisade,  where  a  portion  was  sprayed  with  arsenate  of 
lead,  another  with  the  lime  and  sulfur  wash,  and  a  third  part  left 
with  no  spray.  The  arsenate  of  lead  was  used  at  the  rate  of  5  pounds 
of  the  paste  to  50  gallons  of  water.  The  lime  and  sulfur  wash 
was  used  at  the  rate  of  15  pounds  lump  lime  and  15  pounds  flowers 
of  sulfur  per  50  gallons  of  water,  the  two  ingredients  being  boiled 
together  in  a  small  amount  of  water  for  forty-five  minutes,  then 
diluted  with  enough  cold  water  to  make  fifty  gallons  of  spray.  The 
spraying  was  done  with  a  hand  pump  and  sprayed  trees  thoroughly 
coated  over  all  bark  and  twig  surface.  The  two  sprays,  as  applied, 
were  of  about  equal  cost — each  a  trifle  over  1  cent  per  gallon,  exclu¬ 
sive  of  cost  of  preparation.  The  arsenate  of  lead  spray  was  far  less 
inconvenient,  and  was  quicker  in  preparation,  and  was  also  more 
pleasant  to  prepare  and  apply. 

The  spraying  was  done  on  April  14,  at  which  time  the  majority 
of  the  blossom  buds  showed  their  pink  tips,  but  as  a  rule  were  un¬ 
opened,  with  the  essential  parts  of  the  blossom  still  concealed  by  the 
folded  petals  of  the  flower.  Some  varieties,  however,  in  each  plat 
were  farther  advanced  and  some  with  as  many  as  87  per  cent  of  the 
blossoms  open. 

The  comparative  insecticidal  values  of  the  two  sprays  were  ap¬ 
parent  through  the  season  from  the  number  of  injured  twigs  per 
tree,  and  also  from  the  number  of  gummy  peaches  per  tree  occur¬ 
ring  upon  each  plat. 


FIELD  ENTOMOLOGIST.  „ 

.  A  striking  difference  was  apparent  when  the  number  of  injured 
twigs  per  tiee  weie  bi  ought  into  comparison  by  observations  made 
in  May  and  shown  in  the  following  table : 

A  COMPARISON  BETWEEN  LIME  AND  SULFUR  WASH  AND  ARSENATE  OF 

LEAD  AGAINST  PEACH  TWIG-BORER. 


Spray. 

Date 

Spray¬ 

ed. 

No. 

trees 

spray¬ 

ed. 

No. 

trees 

exam¬ 

ined. 

Date 

exam¬ 

ined. 

] 

t  Total 
No. 
injur¬ 
ed 

twigs 

count¬ 

ed. 

Aver¬ 

age 

No.  in¬ 
jured 
twigs 
per 
tree. 

Per 

Cent. 

Ben¬ 

efit. 

Conclusions. 

Lime  and  Sulfur.... 

14  Apr. 

38 

17 

9-18  My 

72 

4.23 

90 

Good. 

Arsenate  of  Lead.. 

14  Apr. 

3d 

16 

»( 

20 

1.25 

97 

Better. 

Check  . 

No 

spray 

18 

8 

C6 

342 

42.75 

0 

Circumstances  prevented  the  keeping  of  an  exact  record  of  the 
number  of  wormy  peaches  taken  from  each  plat,  but  a  very  notice¬ 
able  difference  was  noted  at  time  of  picking — a  difference  quite  as 
marked  and  corresponding  in  results  with  the  figures  shown  in  the 
above  table.  In  fact,  the  owner  of  the  orchard  invariably  picked 
the  wormy  peaches  from  the  plat  not  treated  and  found  scarcely  any 
fruit  damaged  in  either  of  the  plats  sprayed. 

It  may  be  said  that  arsenate  of  lead,  applied  in  the  spring  at  the 
time  the  buds  of  the  peach  are  beginning  to  open,  will  control  the 
peach  twig-borei  as  effectually  and  cheaply  as  the  lime  and  sulfur 
wash,  up  to  this  time  the  most  universally  used. 

Any  arsenate  of  lead  spray  applied  to  peach  trees  must  not  contain 
free  arsenic,  as  they  are  easily  damaged  by  impure  lead  or  lead  di¬ 
luted  with  watei  to  contain  too  high  a  per  cent  of  the  poison,  though 
puie.  Groweis  using  3  pounds  lead  per  50  gallons  water  were 
equally  successful,  and  from  the  susceptibility  of  peach  to  injury,  this 
latter  strength  is  recommended,  instead  of  the  stronger  spray  used 
in  the  experiment  reported  above. 

PEACH-BORER.  ( Sanninoidea  exitiosa  Say.) 

Disttibution  This  dangerous  insect  has  been  found  present  in 
some  peach  orchards  of  the  Western  Slope. 

Our  species  is  the  same  as  the  one  found  in  Eastern  states,  causing 
such  widespread  damage  to  peach  trees.  It  is  evidently  a  pest  which 
has  come  into  the  orchards  along  with  nursery  stock  brought  to  us 
from  some  infested  part  of  our  country 

Injury  and  Life  History — The  injury  is  one  resulting  from  the 
burrowing  of  a  yellowish-white  larva,  which,  when  fully  grown,  some¬ 
times  measures  one  and  one-fourth  inches  in  length.  Signs ’of  the 
presence  of  the  borer  are  the  gummy  exudations  coming  from  the 
crown  of  the  tree  at  the  top  of  the  ground.  Infested  trees  examined 
early  in  the  summer  showed  larvae  of  sizes  varying  from  one-fourth 
to  one  and  one-fourth  inches  in  length.  Some  small  larvae  were 
then  barely  concealed  beneath  the  peach  gum  on  the  outer  bark. 


12 


COLORADO  EXPERIMENT  STATION. 


Other  larger  larvae  were  within  extensive  chambers,  extending  up  and 
down  through  the  wood,  sometimes  an  inch  beneath  the  bark.  Trees 
badly  infested  are  completely  girdled  and  killed.  The  insects 'spend 
the  winter  as  larvae,  and  in  the  early  summer  change  to  pupae  within 
a  brown  cocoon  or  cell  from  seven-eighths  to  one  inch  long  by  one- 
fourth  to  five-sixteenths  inch  in  diameter,  usually  projecting  into  or 
from  the  gummy  mass  at  the  base  of  the  tree.  The  first  pupa  was 
found  formed  within  these  cocoons  on  the  15th  of  June,  though  the 
majority  were  being  formed  about  the  middle  of  July.  The  pupae 
yield  moths,  the  female  of  which  are  of  a  blackish-brown  color,  with 
partially  transparent  wings  and  a  black  body,  circled  at  about  the 
middle  with  a  beautiful  orange  band.  The  males  are  smaller  and 
more  slender  than  the  females  and  have  a  number  of  smaller,  less 
conspicuous  bands  of  yellow  about  the  abdominal  segments  and  with 
more  nearly  transparent  wings.  The  first  moths  appeared  on  July 
6,  though  the  maximum  number  were  not  appearing  until  about 
August  11,  a  singular  fact,  since  these  moths  are  known  to  come  out 
in  greatest  numbers  in  New  York  state  and  at  Washington,  D.  C., 
from  one  and  one-half  to  two  months  earlier  in  the  season.  Eggs 
are  laid  upon  the  rough  bark  about  the  crown  of  the  tree.  The 
eggs,  when  laid,  are  oval  and  of  a  brown  color.  Large  numbers  are 
deposited  by  each  female.  On  August  6,  a  single  female  gave  by 
dissection  about  400  eggs,  250  of  the  number  at  that  date  being 
brownish  in  color  and  well  formed,  while  150  were  white  and  still 
embryonic  in  nature. 

Experiments  Begun — Its  importance  made  it  seem  advisable  to 
test  remedial  measures,  and  various  old  and  some  new  methods  of 
combatting  the  pest  were  begun  in  June,  and  the  final  results  are  still 
pending. 

Following  are  the  measures  under  comparison  in  the  experiment : 

(1)  Carbon  bisulfide,  1  ounce  per  tree  about  crown. 

(2)  Tobacco  dust,  2  pounds  per  tree  about  crown. 

(3)  Tarred  felt  and  wire  shields  about  base  of  tree. 

(4)  Lime  dust,  2  pounds  to  4  pounds  per  tree  about  base  of  tree. 

(5)  Dirt  removed  and  larvae  removed  by  hand. 

(6)  Banking  earth  about  tree’s  base. 

(7)  Tree  washes. 

(8)  Trees  not  treated  in  same  orchard  to  be  used  as  comparison. 

GREEN  APHIS  OF  APPLE.  {Aphis  pomi.) 

Importance — The  unusual  abundance  of  this  aphid  the  past  sea¬ 
son  upon  apple  and  occasionally  upon  pear  on  the  Western  Slope 
has  made  it  necessary  to  make  observations  upon  and  carry  out  in¬ 
secticidal  tests  against  it. 

Life  History — The  green  aphis  winters  as  eggs  upon  the  twigs 
of  the  tree,  and  the  past  spring  a  very  large  per  cent  withstood  the 
winter.  They  began  hatching  about  Grand  Junction  about  April  I, 
continuing  for  two  weeks  or  more.  The  young  hatched  at  about  the 
same  time  the  first  traces  of  green  foliage  appeared,  and  thus  found 
tender  food  upon  which  to  feed  at  once. 


FIELD  ENTOMOLOGIST.  i3 

In  the  latter  part  of  Apiil  winged  insects  appeared  and  a  general 
spreading  of  the  pest  from  tree  to  tree  and  orchard  to  orchard  took 
place.  Multiplication  was  enormously  rapid.  The  injury  continued 
to  increase  in  severity  through  the  summer.  Lace  wings  and  syr- 
phus  fly  larvae,  as  well  as  the  adults  and  larvae  of  lady  beetles,  served 
to  do  much  good  later  in  the  season,  but  did  not  succeed  in  reducing 
the  aphids  enough  to  prevent  great  injury.  Eggs  of  the  green  aphis 
were  first  found  in  the  fall  at  Grand  Junction  on  October  1 6.  When 
first  laid,  the  eggs  are  green,  but  finally  turn  to  a  glistening  black. 

Injury — They  have  been  a  great  hindrance  to  the  growth  of  young 
apple  trees  set  the  past  spring  or  the  preceding  year,  and  older  trees 
have  not  been  exempt  from  their  attacks.  Missouri  Pippin  apples 
of  all  ages  have  suffered  heavily,  the  aphis  apparently  preferring  this 
variety  to  any  other  common  in  the  Valley  of  the  Grand.  Badly 
infested  trees  through  the  summer  present  a  most  disgusting  ap¬ 
pearance,  the  aphids  becoming  so  numerous  that  the  whole  tree  as¬ 
sumes  a  sticky  coating  of  the  secretion  from  the  bodies  of  the  insect. 
This  “honey  dew”  secretion  attracts  swarms  of  flies  and  ants,  and 
the  trees  often  emit  a  very  disagreeable  odor. 

The  effect  upon  the  tree,  if  young,  is  a  severe  retarding  of  its 
growth.  A  form  of  injury  noted  this  season,  thought  to  be  due  to 
this  insect,  was  an  odd  and  greatly  deformed  growth  of  the  fruit 
itself.  Nero  and  Winesap  apples  were  found  affected  in  this  way. 
The  young  apples,  when  only  from  one-fourth  to  one-half  inch  in 
diameter,  had  been  so  thickly  covered  with  aphids  that  their  growth 
had  been  suddenly  checked.  Later  on,  their  growth  had  been  re¬ 
sumed  principally  from  the  outer  end  of  the  apple,  producing  what 
might  be  called  a  “double  apple,”  with  a  constriction  at  the  middle 
point.  Other  apples  were  caused  to  grow  in  greatly  gnarled  or 
knotted  forms.  All  were  greatly  dwarfed  in  size,  seventeen  Winesap 
apples  at  harvest  time  being  contained,  in  one  instance,  within  a 
common  match  box. 

Treatment — Trees  heavily  infested  had  their  leaves  tightly  curled, 
due  to  the  presence  of  myriads  of  the  aphids  upon  their  under  surfaces.' 
With  the  aphids  thus  concealed  within  the  curled  leaves,  it  was  found 
almost  impossible  to  cover  their  bodies  with  any  contact  spray  ap¬ 
plied,  and  the  practice  of  summer  spraying  against  them  was  any¬ 
thing  but  a  success.  Individual  trees  were,  in  cases,  cleared  up,  but 
other  trees  near  by  and  left  untreated  usually  very  soon  reinfested 
them. 

Spring  and  early  winter  treatments  were  also  carried  out  in 
experiments  against  this  insect. 

The  spring  spraying  was  directed  against  the  eggs  of  the  pest 
and  gave  the  best  promise  of  its  successful  control.  In  an  experi¬ 
ment  with  a  number  of  contact  sprays  applied  April  5,  just  after 
the  eggs  had  begun  to  hatch,  it  was  found  that  the  lime  and  sulfur 
wash  proved  the  most  successful.  In  this  instance,  15  pounds  of 
lime  and  15  pounds  of  sulfur  per  50  gallons  of  water  were  used, 
and  practically  all  of  the  eggs  and  hatched  aphids  were  destroyed. 


14 


COLORADO  EXPERIMENT  STATION. 


In  December,  kerosene  emulsion  and  soluble  petroleum  sprays 
were  given  egg-covered  trees,  and  the  per  cent  of  eggs  destroyed  at 
time  of  hatching  this  spring  will  be  determined.  Further  experi¬ 
ments  for  the  control  of  this  pest  are  planned,  including  a  large  series 
on  contact  insecticides  to  be  used  this  spring. 

WOOLLY  APHIS.  ( Schizoneura  lanigera.) 

Importance — Probably  more  important  to  the  fruit  growers  of 
Western  Colorado  than  the  green  aphis  is  the  woolly  aphis  of  the 
apple.  The  past  season  this  pest  has  ranked  second  only  to  the  cod¬ 
ling  moth  in  destructiveness  in  the  Grand  Valley,  and  has  been  of 
first  importance  in  other  counties  of  the  Western  Slope. 

Life  History — Many  lived  through  the  winter  upon  the  roots 
of  the  apples,  and  a  few  survived  the  winter  upon  the  branches  above 
ground.  During  the  winter  of  1905-06  the  •  temperature  at  Grand 
Junction,  according  to  the  United  States  Weather  Station,  did  not 
drop  as  low  as  the  zero  point,  and  the  unusually  mild  winter  perhaps 
had  much  to  do  in  the  great  abundance  of  the  insect  this  past  summer. 

In  May  many  of  the  aphids  above  ground  had  already  secreted 
their  woolly  coverings  of  white,  and  in  cases  heavily  infested  the 
water  sprouts  about  the  base  of  the- tree.  By  the  month  of  July, 
countless  myriads  of  them  were  to  be  seen  crawling  over  all  parts 
of  the  tree  and  fruit,  as  well  as  upon  the  ground  through  the  orch¬ 
ards.  Winged  ones  were  noted  first  at  Fruita  September  6. 

Parasites — Parasites  have  done  some  service  in  helping  to  keep 
in  control  the  pest,  but  have  not  been  abundant  enough  to  reduce 
the  number  of  insects  to  a  point  below  injury.  Lace  wing  and  syr- 
phus-fly  larvae,  as  well  as  adults  and  larvae  of  lady  beetles,  have  been 
most  prominent  in  preying  upon  this  aphis.  Some  observations  upon 
the  habits  and  life  history  of  these  parasites  have  been  made. 

Injury — Roots  and  tops  were  attacked  throughout  the  season,  the 
twigs  being  sometimes  entirely  coated  with  the  woolly  secretion  cov¬ 
ering  the  bodies  of  the  insects.  Such  infested  twigs  were  greatly 
dwarfed,  the  bark  on  the  twigs  caused  to  split  and  grow  in  a  gnarled 
and  misshapen  form.  The  "honey  dew”  secretion  from  the  insects 
in  some  cases  coated  over  the  peeling  of  the  fruit  itself,  leaving  the 
surface  so  sticky  and  discolored  that  apples  were  disgusting  in  ap¬ 
pearance  and  most  unpleasant  to  handle.  Grafts  and  top-worked 
trees  suffered  most  heavily  in  the  spring,  and  their  injury  continued 
through  the  summer. 

So  thick  were  the  insects  upon  the  branches  that  apple  pickers 
working  in  the  trees  had  their  clothing  covered  with  crushed  bodies 
and  the  white  secretion  of  the  insect. 

Roots  about  the  crown  of  the  trees  were  gnarled  and  knotted, 
resulting  in  the  dwarfing  of  the  trees,  the  production  of  undersized 
fruit,  and,  in  exaggerated  cases,  the  outright  destruction  of  the  trees 
themselves. 

Experiments  in  Progress — Summer  sprays,  as  with  the  green 
aphis,  where  the  infestation  was  so  severe  and  so  general  through 
the  orchards,  proved  of  small  practical  value. 


FIELD  ENTOMOLOGIST. 

V/ 

>  This  pest  is  of  such  importance  that  careful  and  exhaustive  ex 

S  »S“«  .!.«m 

aeiay.  in  the  fall  and  early  winter  a  lone  list  of  inserH- 
Cl  es  were  applied  to  infested  trees,  and  the  list  will  be  duplicated 
this  coming  spring,  and  it  is  hoped  that  by  the  comm-  fan  some 
practical  suggestions  upon  an  effective  method  of  controfof  the  nest 
may  be  reported.  Tobacco  and  carbon  bisulfide  upon  the  roots  of  the 
rees,  and  kerosene  emulsion,  whale  oil  soap,  and  tobacco  decoct  on 

byTrchardTe, TTh"  ^  ^  the,  Previo'ls  Prices  of  SS 
o-iw  u ™  i  ,  h  measures,  soluble  petroleum  sprays,  tree  tan- 

ough  trkl  and  many  °ther  methods  of  contro1  will  be  given  thor- 

A  NEW  INJURY  TO  PEAR  AND  APPLE  BUDS 

Description— On  the  4th  of  May,  an  injury  to  buds  of  near  on 

Att  fnfP  aCfd  ont°  P6ar  u°Cks  about  one  month 'earlier  was  observed 
;  ttention  to  the  injury  had  been  called  by  the  owner  of  the  -rafted 

trees,  who  had  observed  that  his  grafts,  which  should  have  been 

starting  readily  off  into  growth,  were  being  held  back  by  some  insect 

grow!  apparent  y  was  eatlnS  away  the  buds  as  soon  as  they  started  to 

Examination  on  May  4  showed  the  injury  to  be  caused  bv  a  tinv 
chrysomehd  beetle  ( Myochrous  squamosus  LeC.)  greyish-brown  in 
color  and  less  than  one-fourth  inch  long.  No  published  accounts  of 

TlTtf  Li1”5  kind  from  this  beetle  have  been  found,  and  it  is  prob- 
he^IphaTf  118  ob,servatl°"  of  mjmy  is  the  first  recorded  against  the 
etle.  It  caused  enough  trouble,  however,  to  require  some  remdial 
measures  Unless  something  had  been  done  greater  damage  would 
have  resulted,  and,  as  it  was,  some  of  the  attacked  grafts  were  de- 
stroyed  by  having  all  buds  eaten  away. 

The  beetles  were  discovered  about  the  bases  of  the  grafted  pear 
trees,  hiding  beneath  clods  and  in  crevices  of  the  earth.  The  principal 
injury  was  done  to  pear  buds,  though  specimens  were  also  taken 
ee  mg  upon  the  buds  of  apple  borne  by  twigs  near  the  ground. 

nniet  rLTur6K  t  foUn,d  beneath  cIods  about  the  apples.  Not 
only  did  the  beetles  attack  the  buds  upon  grafts,  but  they  were  found 

eating  into  the  pear  leaf  and  fruit  buds  high  up  into  the  tree  In 

one  instance,  a  beetle  was  watched  eating  away  the  petals  of  an  open 

pear  btossom.  Search  was  made  about  the  trees  for  a  weed  or  plant 

which  could  have  served  as  a  natural  food  plant  for  either  adult  or 

larvse,  but  none  was  found.  As  many  as  a  dozen  beetles  were  in 

cases,  collected  about  the  grafts  of  a  single  small  tree  or  about 'the 

base  of  the  tree.  The  injury  continued  through  the  month  of  May 

and  beetles  kept  in  cages  at  my  insectary  were  kept  alive  through  the 

month .  of  June.  Many  of  the  beetles  were  found  floating  on  the 

water  in  irrigating  ditches  late  in  May,  and  later  adults  were  taken 

hiding  beneath  bands  placed  upon  trees  to  capture  codling  moth  larvse. 

Control  Several  measures  of  control  were  suggested  or  used.  A 

spray  of  arsenate  of  lead  applied  to  the  buds  was  tried  and  thought 

to  have  been  of  considerable  benefit.  The  owner  of  the  orchard  prac- 


l6  COLORADO  EXPERIMENT  STATION. 

ticed  hand  picking  of  the  beetles,  but  the  process  would  be  entirely 
impracticable  upon  any  number  of  trees.  The  winged  beetle  ap¬ 
peared  to  be  more  of  a  crawling  insect  than  a  flying  one,  which  sug¬ 
gested  the  possibility  of  protecting  young  grafts  by  placing  bands  of 
“Tree  Tanglefoot”  or  other  adhesive  bands  about  the  tree  trunks 
to  keep  the  beetles  from  ascending  in  the  spring. 

MISCELLANEOUS  OBSERVATIONS. 

A  great  many  other  injuries  to  fruit  or  field  crops  by  insects, 

rodents,  etc.,  were  observed  through  the  season.  . 

\  pink-bodied  aphis  of  undetermined  species  was  found  doing  con¬ 
siderable  damage  to  peach  buds,  blossoms,  and  young  fruit  early  in 
the  spring.  Specimens  were  first  seen  April  13,  at  which  time  peaches 
were  showing  first  bloom.  The  larger,  flat-bodied,  pinkish  aphis  first 
observed  gives  birth  to  young,  which  cluster  about  the  blossoms  and 
about  the  forming  peaches,  still  very  small  sucking  fF0^ 
sap  and  causing  many  to  fall  to  the  ground.  Later  m  the  season, 
peach  leaves  are  curled  up  by  the  aphids,  but  all  seem  to  djsappw 
late  in  May.  The  injury  is  thus  done  early  in  the  season  at  the  time 
fruit  is  setting.  Application  of  the  lime  and  sulfur  wash  just  before 
the  buds  open  is  suggested  as  a  means  of  control,  and  this  and  ot  e 

measures  of  treatment  will  be  tried  in  an  experimental  way  the  com- 
•  • 

Observations  were  also  made  upon  aphids  infesting  plums,  elms, 

Injuries  to  cantaloupes  were  noted,  caused  by  leaf  miners,  the 
common  red  ant  of  the  prairies,  and  prairie  dogs.  In  some  orchards 
the  green  fruit  worm  caused  injury  to  from  io  to  25  per  cent  of  the 
young  forming  apples,  but  in  orchards  receiving  proper  codling  moth 
spraying  the  injury  is  much  less  severe  or  reduced  beneath 

A  pear  leaf  blister  mite,  probably  of  a  different  species  from 
that  causing  the  injury  in  Eastern  States,  was  observed  in  great  num¬ 
bers  through  the  summer,  causing  the  blackened  curling  of  the  pear 
leaves  at  the  tip  of  the  twigs,  as  well  as  producing  minute  blisters 
upon  the  leaves  and  causing  them  to  drop  from  the  trees  prema¬ 
turely.  It  is  thought  that  a  late  spring  spray  with  the  lime  and  sul¬ 
fur  wash  will  also  control  this  pest.  .  , 

Other  orchard  pests  observed,  studied,  or  experimented  upon 
in  attempt  at  control  were  the  buffalo  tree  hopper,  tent  caterpillar, 
hawk  moth  larvae,  grasshoppers,  thrips,  brown  mite,  pear  and  cherry 
slug,  terrapin  scale,  Putnam  scale,  and  numerous  parasitic  or  preda- 
cbus  insects  doing  beneficial  service  in  the  orchards. 


Bulletin  1 20 


July  1907 


The  Agricultural  Experiment  Station 

- OF  THE - 

Colorado  Agricultural  College 


The  Howard  Scale 


ESTES  P.  TAYLOR 


PUBLISHED  BY  THE  EXPERIMENT  STATION 
Fort  Collins,  Colorado 


I 


The  Agricultural  Experiment  Station. 

FORT  COLLINS,  COLORADO 


THE  STATE  BOARD  OF  AGRICULTURE 


TERM 

EXPIRES 


Hon.  JAMES  L.  CHATFIELD . 

Hon.  B.  U.  DYE . 

Hon.  B.  F.  ROCKAFELLOW,  President 

Hon.  E.  H.  GRUBB . 

Hon.  R.  W.  CORWIN . 

Hon.  A.  A.  EDWARDS . 

Hon.  F.  E.  BROOKS . 

Hon.  J.  L.  BRUSH . 


Gypsum . 1909 

Rocky  Ford . 1909 

Canon  City . 1911 

Carbondale . 1911 

Pueblo . . 1913 

Fort  Collins . 1913 

Colorado  Springs. .  .1915 
.  Greeley . 1915 


Governor  HENRY  A.  BUCHTEL,  )  ~  . 

President  BARTON  O.  AYLESWORTH,  )  ex-°JJlC10 


A.  M.  HAWLEY,  Secretary  EDGAR  AVERY  Treasurer 

Executive  Committee  in  Charge 

B.  F.  ROCKAFELLOW,  Chairman. 

A.  A.  EDWARDS.  B.  U.  DYE. 


STATION  STAFF 

L.  G.  CARPENTER,  M.  S.,  Director . Irrigation  Engineer 

C.  P.  GILLETTE,  M.  S . . . . Entomologist 

W.  P.  HEADDEN,  A.  M.,  Ph.  D . Chemist 

WENDELL  PADDOCK,  M.  S . Horticulturist 

W.  L.  CARLYLE,  M.  S.  . .  . Agriculturist 

G.  H.  GLOVER,  M.  S.,  D.V.  M . Veterinarian 

W.  H.  OLIN,  M.  S., . * . Agronomist 

R.  E.  TRIMBLE,  B.  S . Assistant  Irrigation  Engineer 

F.  C.  ALFORD,  M.  S . . Assistant  Chemist 

EARL  DOUGLASS,  M.  S . Assistant  Chemist 

S.  ARTHUR  JOHNSON,  M.  S .  .Assistant  Entomologist 

B.  O.  LONGYEAR,  B.  S .  Assistant  Horticulturist 

E.  B.  HOUSE,  M.  S  . Assistant  Irrigation  Engineer 

F.  KNORR . Assistant  Agronomist 

P.  K.  BLINN,  B.  S . Field  Agent,  Arkansas  Valley,  Rocky  Ford 

E.  R.  BENNETT,  B.  S . . Potato  Investigations 

Western  Slope  Fruit  Investigations,  Grand  Junction: 

O.  B.  WHIPPLE,  B.  S . Field  Horticulturist 

E.  P.  TAYLOR,  B.  S . Field  Entomologist 


OFFICERS 

President  BARTON  O.  AYLESWORTH,  A.  M.,  LL.  D. 


L.  G.  CARPENTER,  M.  S . Director 

A.  M.  HAWLEY . Secretary 

A^UUP  MURRA  Y . Clerk 


THE  HOWARD  SCALE. 

Jlspidiotus  howardi  C/^II. 

- by - 

ESTES  P.  TAYLOR. 


INTRODUCTION. 

The  extensive  injury  wrought  in  parts  of  the  State  of  Colorado 
to  pear,  prune,  plum  and  other  fruit  and  shade  trees  by  this  insect 
makes  it  one  of  especial  interest  to  the  horticultural  industry  at  this 
particular  time.  Further,  the  pest  is  the  nearest  ally  of  San  Jose  or 
Chinese  Scale,  well  known  as  the  most  destructive  of  all  fruit  tree 
enemies.*  The  Howard  Scale  is  one  of  peculiar  importance  to  fruit 
growers  of  this  state  since  its  first  discovery  was  made  in  Colorado 
and  fruit  growers  of  no  other  state  as  yet  consider  the  pest  with  the 
same  degree  of  interest.  So  far  as  is  known,  two  states  only,  Colorado 
and  New  Mexico,  harbor  this  insect. 

The  history  of  the  insect  is  all  of  comparatively  recent  date.  It 
was  first  discovered  by  Prof.  C.  P.  Gillette  at  Canon  City,  on  August 
31,  1894,  upon  the  fruit  and  bark  of  prune  and  wild  plum.  These 
first  specimens  were  sent  to  Dr.  L.  O.  Howard  of  the  Bureau  of  Ento¬ 
mology,  U.  S.  Department  of  Agriculture  and  to  Prof.  T.  D.  A.  Cock¬ 
erell,  then  of  the  New  Mexico  Agricultural  Experiment  Station,  but 
now  of  the  State  University  of  Colorado  at  Boulder.  Dr.  Howard 
pronounced  the  insect  a  new  species  and  Professor  Cockerell  applied 
to  it  the  name  Howard  scale.* 

Professor  Cockerell  later  encountered  the  scale  at  Albuquerque, 
New  Mexico,  in  August,  1895,  upon  the  fruit  of  silver  prune  which 
determination  was  verified  by  Mr.  Pergande  of  the  U.  S.  Department 
of  Agriculture,  from  material  furnished  him. 

The  next  published  mention  of  it  is  from  Professor  Gillette  in  the 
Annual  Report  of  the  Experiment  Station  for  1901  when  he  reported 
its  occurrence  for  the  first  time  upon  fruit  trees  of  the  Western  Slope. 
Mr.  H.  E.  Mathews,  horticultural  inspector  for  Delta  county  had, 
during  that  season,  sent  specimens  of  the  scale  taken  from  pear  and 


*  A  most  exhaustive  and  complete  treatise  on  “The  San  Jose  or  Chi¬ 
nese  Scale”  has  recently  been  issued  by  Mr.  C.  L.  Marlatt  as  Bulletin  No. 
62,  Bureau  of  Entomology,  U.  S.  Dept,  of  Agriculture.  This  bulletin  should 
be  in  the  hands  of  every  Colorado  fruit  grower.  It  may  be  had  by  applica¬ 
tion  to  the  U.  S.  Dept,  of  Agriculture,  Washington,  D.  C. 

*  The  original  description  was  published  in  Canadian  Entomologist,. 
XXVII  p.  16  (1895).  Prof.  Wilmon  Newell  published,  in  1899,  from  Iowa, 
Contributions  from  Dept,  of  Zoology  and  Entomology,  No.  3  Iowa  State 
College,  an  article  upon  “The  North  American  Species  of  the  Sub-genera 
DiaspicLiotus  and  Hemiberlisia.  of  the  genus  Aspidtous ”  including  Prof. 

.  Cockerell's  original  description  of  A.  howardi  Ckll.  and  giving  as  its 
habitat  Colorado  and  New  Mexico.  More  recently  it  has  been  given  posi¬ 
tion  in  “Tables  for  the  Identification  of  Rocky .  Mountain  Coccidae”  (scale 
insects  and  mealy  bugs),  published  by  Prof.  Cockerell. 


4  THE  COLORADO  EXPERIMENT  STATION 

plum  trees  severely  attacked.  In  the  report  for  1902  Professor  Gil¬ 
lette  reported  his  discovery  of  it  upon  the  leaves  of  white  ash  trees 
in  Denver. 

Though  the  insect  has  been  previously  reported  in  various  ento¬ 
mological  publications,  and  notes  have  been  given  upon  habits  and 
portions  of  its  life  history,  nothing,  up  to  the  present  bulletin,  has  been 
published  upon  its  control. 

In  Mesa  county  the  Howard  scale  was  found,  by  the  writer,  to 
be  doing  much  damage.  It  was  found  in  practically  all  localities  where 
its  food  plants  were  known  and  at  elevations  above  sea  level  varying 
from  something  over  4,000  feet  to  nearly  7,000  feet.  Dr.  S.  M. 
Bradbury,  horticultural  inspector  for  Mesa  county,  reports  that  what 
he  has  taken  to  be  Howard  ScaT  has  been  known  in  the  Grand  \ralley 
as  a  pest  upon  pears  and  other  fruits  since  they  were  first  grown 
here.  In  many  instances  fruit  growers  observing  the  infestation  of 
their  trees  by  a  scale  insect  had  suspected  the  presence  of  San  lose 
scale,  while  others  supposed  it  to  be  the  Putnam  scale  common  in  other 
states  upon  certain  shade  and  fruit  trees. 

The  fruit  growers  and  fruit  growers’  associations  of  the  Grand 
valley  have  given  hearty  co-operation  in  offering  their  orchards  and 
mater. als  for  experimentation  and  otherwise  aiding  in  bringing  new 
data  to  light.  Also  acknowledgements  are  due  members  of  the  Bureau 
of  Entomology  at  Washington  for  cuts  furnished  and  determinations 
made ;  to  Miss  Miriam  A.  Palmer,  entomological  artist,  of  the  Experi¬ 
ment  Station  for  original  drawings  of  the  insect,  and  to  Professor  Gil¬ 
lette  for  valuable  suggestions  and  much  special  assistance  given. 

FOOD  PLANTS. 

Notwithstanding  the  occurrence  of  this  insect  upon  shade  as  well 
as  fruit  trees  it  is  primarily  an  economic  pest  of  the  latter.  In  my 
•observations  it  has  been  taken  upon  the  following  fruit  trees :  pear, 
prune,  plum,  almond,  apple  and  peach.  By  far  the  greatest  injury 
has  been  done  to  pear  and  by  many  orchardists  it  is  popularly  called 
the  ‘'pear  scale.” 

Bartlett  pears  seem  to  be  most  commonly  infested  of  varieties 
grown  in  Colorado.  Certain  varieties  of  fruit  will  often  become  heavily 
infested  and  require  spraying  long  before  sorts  more  nearly  immune 
show  any  noticeable  number  of  the  scales. 

Next  to  the  near,  the  prunes  and  plums  seem  to  be  the  most  suscep¬ 
tible.  It  seems  that  Wild  Goose  and  other  varieties  of  American  plums 
show  infestation  more  generally  than  the  Japanese  varieties.  Silver 
prune  trees  are  often  found  encrusted.  Almonds,  though  grown  to  a 
limited  extent  in  Western  Colorado,  seem  to  be  quite  susceptible  to 
its  ravages. 

It  is  rather  the  exception  than  the  rule  to  find  apples  attacked. 
A  singular  preference  is  shown,  however,  for  the  Grimes  Golden. 
Scores  of  instances  have  been  noted  where  trees  of  this  variety  show 
infestation  and  other  varieties  growing  near  by  are  totally  exempt. 


THE  HOWARD  SCALE 


5 

Slight  infestation  has  also  been  found  upon  Bailey  Sweet,  White 
Winter  Pippin,  Snow  and  Jeneton. 

Peach  trees  are  practically  exempt,  probably  only  becoming  slightly 
infested  when  standing  very  close  to  other  varieties  which  are  more 
commonly  attacked.  This  is  of  rare  occurrence,  peaches  and  most 
varieties  of  apples  being  practically  uninjured  by  the  insect — a  singu¬ 
lar  fact  in  consideration  that  the  San  Jose  scale  is  most  destructive 
to  peaches  and  apples.  Numerous  cases  are  known  of  its  existence 
upon  native  plum  trees  growing  in  the  state.  Of  the  shade  trees  re¬ 
ported  infested,  we  have  the  white  ash  and  the  maple,  the  latter 
reported  by  Professor  Cockerell. 

From  its  appearance  only  in  the  two  states  named  it  seems  prob¬ 
able  that  it  originally  lived  upon  native  trees  or  plants  and  found 
suitable  food  upon  the  fruit  trees  planted  adjacent  to  them  in  recent 
years. 


NATURE  OF  DAMAGE. 

Injuries  from  this  insect  are  seen  in  the  dwarfing  of  the  trees 
robbed  of  their  sap.  crack'ng  the  bark,  killing  the  tree  outright, 
and  in  an  unsightly  pitting  of  the  surface  of  the  fruit  with  discoloration 
about  the  points  of  scale  attachment.  Upon  the  greener  portion  of 
the  pears,  the  side  shaded  during  growth,  this  reddening  is  more 
noticeable  than  upon  the  sun-exposed  side.  Some  of  the  pits  or  inden¬ 
tures  contain  single  scales  and  some  bear  clusters  of  several.  In  the 
case  of  yellow-skinned  plums  these  reddened  blotches  about  the  scale 
are  most  noticeable  and  objectionable.  With  dark  colored  plums,, 
prunes  and  pears,  the  scales  appear  as  many  small  white  specks  scat¬ 
tered  over  the  surface  (plate  I,  fig.  V).  With  the  pear,  deep  pits 
are  also  found  in  the  skin,  with  Bartletts  some  of  these  measure 
nearly  one-fourth  inch  deep  and  as  wide  across  at  the  top.  (See 
plate  I,  figs.  V.  and  VI).  More  often  the  scales  are  grouped  into 
clusters  about  the  calyx  or  stem  end  of  the  fruit.  All  fruit  so  injured 
is  excluded  from  the  fancy  grades  and  placed  in  the  cheaper  ones  if 
not  rejected  entirely. 

Early  descriptions  of  the  insect  gave  it  as  a  pest  principally 
upon  the  fruit  instead  of  the  tree.  The  tendency  to  infest  the  fruit 
is  perhaps  greater  than  with  other  closely  related  scale  insects,  but 
the  attack  is  also  directed  to  bark,  twigs  and  leaves.  A  marked  ten¬ 
dency  is  shown  for  the  insects  to  crowd  outward  to  the  tips  of  the 
branches  where  the  bark  is  more  easily  pierced  by  them  or  where  more 
succulent  and  tender  tissue  such  as  leaves  or  fruit  is  available. 

When  the  twigs  become  heavily  infested  with  the  scales  they  may 
almost  hide  the  bark  as  shown  in  the  prune  twig  in  plate  I,  fig.  IV. 
If  allowed  to  go  unchecked  upon  trees  most  susceptible  to  their  attack, 
the  result  will  be  a  complete  coating  over  the  bark  with  an  incrustation 
of  the  bodies  of  the  insects  and  their  scale  secretions.  Trees  allowed  to 
remain  in  this  condition  might  be  completely  killed,  and  would  bear 
only  scale-covered  fruit  and  eaves.  The  fruit  would  be  quite  unmar¬ 
ketable  and  the  leaves,  browned  and  impoverished  by  their  sap  sucking 


6 


THE  COLORADO  EXPERIMENT  STATION 


parasites,  would  drop  from  the  trees  prematurely.  Before  spraying 
became  generally  adopted  in  the  Grand  Valley,  the  products  of  whole 
pear  orchards  were  rendered  unmarketable. 

DESCRIPTION  AND  LIFE  HISTORY. 

This  scale  belongs  to  that  class  of  insects  receiving  their  food  by 
sucking  the  juices  of  the  plants  to  which  they  are  attached.  Having 
no  mouth  parts  with  which  to  chew  their  food,  stomach  poisons  or 
arsenical  sprays  are  without  value  applied  to  them.  They  must  be 
controlled  by  contact  sprays.  They  are  of  minute  size  and  many 
times  when  but  moderately  abundant  upon  trees  escape  notice  except  by 
the  trained  observer.  Every  fruit  grower  should  acquaint  himself 
with  the  appearance  of  the  pest  and,  if  possible,  be  able  to  distinguish 
it  from  its  nearest  relatives.  This  will  not  always  be  possible  for  the 
average  orchardist  and  it  will  be  advisable  to  send  samples  of  scale 
insects  found  upon  the  trees  to  the  entomologist  of  the  Agricultural 
Experiment  Station,  for  determination.  This  should  be  done  to  avoid 
the  mistake  of  maintaining  more  dangerous  forms  of  insects  which 
might  be  introduced  by  chance.  The  figures  of  Plate  2  show  the 
insect  drawn  from  life,  but  enlarged,  represent  its  various  stages,  de¬ 
tails  of  structure  and  general  appearance  and  will  aid  in  the  deter¬ 
mination  of  the  species. 

The  male  is  the  only  form  bearing  wings  and  it  is  winged  only 
upon  becoming  adult.  All  females  and  the  males  throughout  the 
greater  part  of  the  year  spend  their  lives  attached  and  immovable  upon 
the  bark,  leaves  or  fruit  and  it  is  during  this  time  that  the  damage  to  the 
host  plant  is  done.  It  is  during  this  period  of  their  lives  that  the  hard, 
scaly  coating  forms  over  them  as  a  protecting  covering.  The  scales  are 
secretions  from  the  body  of  the  insect  concealed  beneath.  A  short 
period  is  spent  by  both  sexes  crawling  over  the  surface  of  the  tree 
or  its  fruit  before  settling  down  for  feeding.  This  period  ,of  but  a 
few  days  duration  at  most,  follows  the  hatching  of  the  young  from 
eggs  deposited  beneath  the  scales.  At  this  time  the  very  minute 
insects  are  scattered  over  the  infested  bark,  appearing  to  the  naked 
eye  as  mere  specks  of  yellow  orange  dust.  They  are  much  smaller  than 
newly  born  young  San  Jose  scale.  For  so  small  an  insect  they  are  very 
active.  One  under  observation  traversed  a  distance  of  one-half  inch 
in  one  minute.  When  it  finally  settles  down  it  inserts  its  beak  through 
the  epidermis  of  the  plant  and,  if  a  female,  from  that  time  to  its 
death  does  not  move.  If  a  male,  it  remains  stationary  through  its 
development  to  the  adult  and  then  equipped  with  wings,  comes  out 
from  beneath  its  covering  for  the  fertilization  of  the  full  grown  females 
still  beneath  their  scales. 

When  first  attaching  itself  to  the  bark  the  secretion  of  the  scaly 
covering  commences.  The  newly  settled  individuals  appear  as  very 
small  white  specks,  as  at  that  time  the  white  fibers  of  the  secretion  have 
not  yet  become  matted  together  nor  assumed  the  darker  hues.  The 
female  scale  in  developing  assumes  a  circular  outline  and  lies  slightly 
convex  upon  the  surface.  Individually  when  matured,  it  is  of  a  pale 


THE  HOWARD  SCALE  7 

grayish  color,  much  lighter  than  the  partially  matured  or  even  fully 
grown  female  of  San  Jose  scale.  The  female  insect  when  fully  grown 
is,  in  diameter  considerably  less  than  the  head  of  a  common  pin. 
She  is  orange-yellow  in  color,  and  broadly  pyriform  or  pear-shaped. 
It  is  only  through  a  higher  power  of  the  microscope  that  the  char¬ 
acteristic  markings  at  the  tip  of  the  abdomen  (Plate  2,  figs.  I  and  II). 
distinguishing  this  insect  from  such  close  relatives  as  the  Putman  or 
San  Jose  scales,  can  be  observed.  The  male  scales  are  more  elongate 
than  the  female  scales,  being  oval  in  outline  and  often  much  darker  in 
color.  The  male  insects  when  fully  grown  and  emerged  are  winged, 
of  very  minute  size,  and  pale  yellowish  brown  in  color  with  black  eyes 

which  show  plainly  in  the  developing  pupa  while  still  beneath  the 
scale. 

The  chief  difference  in  the  general  appearance  of  Howard  scale 
from  its  nearest  allies  is  in  the  distinct  pallidness  of  many  of  the  scales.* 

Badly  infested  trees  have  a  grayish  appearance  over  their  bark 
much  as  if  a  layer  of  ashes  covered  the  tree.  When  rubbed,  this  gives 
the  surface  a  greasy  or  buttery  appearance  caused  by  the  crushing 
of  the  bodies  of  myriads  of  the  yellowish  parasites  which  had  been  se¬ 
creted  beneath  their  grayish  armors.  Orchardists  should  be  able  to 
detect  their  presence  long  before  the  infestation  has  reached  this 
stage.  At  first  appearance,  individual  scales  upon  the  bark  will  exhibit 
only  inconspicuous  grayish  dots.  If  upon  the  branches  of  the  apple, 
these  dots  will  be  surrounded  by  reddened  areas  in  the  bark,  which 
will  be  noticed  before  the  insect  is  seen.  If  upon  the  twigs  of  fruit 
.  trees  other  than  apple  these  reddened  blotches  in  the  bark  will  be 
less  noticeable. 

>  The  winter  is  spent  as  immature  insects.  On  March  19,  in  the 
spring  of  1906,  some  female  scales  were  found  well  grown  and  pale 
gray  to  dark  brown  in  color.  Others  among  these  were  smaller  in 
size,  some  circular  and  some  oval  in  outline.  All  smaller  sized  scales 
near  their  centers  showed  a  whitish  area,  in  some  cases  dusky  gray. 
In  the  center  of  the  white  area  which  occupied  about  one-third  of  the 
surface  of  the  scale  covering,  a  small  whitish  nipple  was  seen  sur¬ 
rounded  by  a  rather  shallow  or  indistinct  furrow  or  ring.  Both  ring 
and  nipple  were  much  less  conspicuous  than  in  the  case  of  San  Jose 
scale  at  this  stage.  On  account  of  the  weathering,  most  of  them 
showed  their  summits  as  smooth  or  bald  areas  reddish  or  orange  in 
color.  The  oval  male  scales  were  found  to  yield  adults  as  early  as  April 


*The  original  description  of  the  insect  as  published  by  Prof.  Cockerell 
in  Can.  Ent.  XX VI I  p.  16,  1895.  is  as  follows: 

Asp idiotus  howardi  n.  sp.-— Female  scale,  circular,  flat,  about  iy2  mm. 
diam.,  pale  grayish  with  a  slight  reddish  tinge;  exuviae  sublateral,  covered, 
dull  orange  secretion  over  exuvie  easily  rubbed  off 

Female  broadly  pyriform,  orange;  margin  of  terminal  portion  thick¬ 
ened,  very  finely  striate  showing  a  violet  color  in  some  lights.  Plates  spine¬ 
like,  spai  ingly  branched.  Median  lobes  very  large  and  prominent,  close 
together  but  not  contiguous,  obliquely  truncate,  slightly  crenate.  Second 
pair  of  lobes  small,  broad  and  low.  Third  pair  practically  obsolete.  There 
are  conspicuous  wax  ducts.  See  Plate  2,  Fig.  ia. 


8  THE  COLORADO  EXPERIMENT  STATION 

3  in  the  orchard,  at  which  time  several  winged  specimens  were  seen  in 
process  of  fertilizing  the  matured  females.  Examination  of  infested 
trees  at  Grand  Junction,  February  9,  1907,  showed  the  male  larvae 
beneath  the  scales  already  with  their  black  eyes  apparent.  No  pupae 
were  yet  formed.  Material  taken  indoors  upon  twigs  has  yielded  males 
as  early  as  February  22.  The  males  seemingly  emerge  throughout 
the  greater  part  of  the  summer. 

Early  in  June  many  newly  hat:hed  insects  of  both  sexes  were 
beginning  to  crawl  actively  over  the  bark.  By  June  9  many  had  set¬ 
tled  down,  thickly  covering  the  bark  with  the  early  summer  brood.  Some 
were  upon  the  small  pears  also  and  .others  were  seen  upon  the  upper 
and  lower  leaf  surfaces.  Many  at  this  date  had  well  developed  scale 
coverings  already  secreted  over  them.  Oval  eggs,  pale  yellow  and  with 
blunt  ends,  were  found, showing  the  females  to  be  oviparous  rather 
than  viviparous  as  in  the  case  of  the  San  Jose  scale.  The  exact  time 
required  for  hatching  is  evidently  short  for  through  the  summer  are 
usually  to  be  seen  from  one  to  a  dozen  minute  yellowish-orange 
colored  and  newly  hatched  young. beneath  each  of  these  scale  coverings 
along  with  small  clusters  of  eggs.  In  cases,  no  eggs  but  only  dusters 
of  the  very  minute  young,  are  to  be  found  beneath  the  female  scales  and 
it  has  been  suggested  by  Professor  Gillette  that  they  are  occasionally 
born  living. 

In  Western  Colorado  it  is  probable  that  at  least  three  and  perhaps 
four  generations  are  developed  during  the  season,  including  those 
living  through  the  winter  in  an  immature  stage.  These  generations, 
however,  greatly  overlap  one  another  making  a  continuous  succession 
of  individuals  appearing  throughout  the  season. 

MEANS  OF  DISTRIBUTION. 

The  most  common  method  of  distribution  of  scale  insects  over 
long  distances  is  well  known  to  result  from  the  shipment  of  infested 
nursery  stock.  Since  almost  all  of  the  new  orchard  plantings  within 
the  state  are  of  nursery  stock  from  states  free  from  this  pest,  and  as 
little  nursery  stock  is  shipped  away  at  present,  this  phase  of  the 
question  does  not  appear  to  be  of  any  particular  consequence. 

The  local  transmission  of  the  insect  is  largely  dependent  upon 
outside  forces  as  the  only  time  during  which  the  female  has  power 
of  locomotion  is  for  the  short  period  from  its  hatching  beneath  the 
scale  covering  to  the  time  it  settles  down  to  feed  at  a  fixed  point 
upon  the  plant.  This  interval  of  activity  is,  however,  of  short  dura¬ 
tion  and  no  great  distance  can  be  traversed  in  the  time  by  so  small 
an  insect.  Except  for  dispersal  over  single  trees  the  insect  must 
depend  upon  outside  agencies  in  spreading.  Such  agencies  are  the 
wind,  other  crawling  and  flying  insects  upon  the  trees,  as  ants  and 
lady  beetles,  birds  and  chickens  or  live  stock  at  large  in  orchards. 
Irrigation  ditches  evidently  transport  the  minute  active  individuals 
which  have  been  blown  or  washed  from  infested  trees.  It  is  also 
likely  that  the  common  operations  of  the  orchard,  such  as  cultivation. 


l’J.ATK  I 


10 


THE  COLORADO  EXPERIMENT  STATION 


pruning-  and  picking  of  fruit  serve,  to  some  extent,  to  carry  the  movable 
ones  from  one  tree  to  another. 

The  effect  of  an  infested  orchard  in  infesting  surrounding 
orchards  is  one  of  the  most  serious  phases  of  the  problem.  On  account 
of  this  scale  spreading  so  slowly,  it  is  noteworthy  that  well  directed 
efforts  of  control  are  likely  to  be  followed  by  quicker  and  more  last¬ 
ing  results  than  when  orchardists  wage  warfare  against  more  active 
insects. 


Howard  scale  parasite,  Prospalta  anrantii  How.,  greatly  enlarged. 

After  L.  O.  Howard,  Bur.  of  Ent.,  Washington,  D.  C. 

NATURAL  ENEMIES. 

In  a  count  made  upon  badly  infested  pear  trees  March  19,  1906, 
of  a  large  number  of  scales,  about  31  per  cent  contained  no  living 
insect.  This  did  not,  however,  correctly  represent  the  natural  mortality 
of  the  insects  due  to  weathering.  Some  of  the  dead  scales  resulted 
from  parasitic  or  predatory  insects. 

Early  in  June  and  again  in  the  month  of  August  adults  of  an 
interesting  little  bee  parasite  were  observed.  Specimens  were  deter¬ 
mined  as  Prospalta  aurantu  How.,  and  the  observation  according  to 
Dr.  L.  O.  Howard  is  the  first  record  of  the  parasite  infesting  "this 
insect.  The  minute  bee  develops  within  the  body  of  the  insect  and 
eats  a  small  round  hole  through  the  scale  where  it  makes  its  escape. 
Dr.  Howard  reports  that  th's  parasitic  bee  has  been  reared  from  San 
Jose  scale  and  is  effective  against  nine  other  species  of  scale  insects 
common  in  different  parts  of  the  United  States.  A  cut  of  the  adult 
parasite  is  shown,  greatly  enlarged,  in  Fig.  1. 

Adult  and  larvae  of  a  common  lady  beetle,  Chilocorus  bivulnerus , 
also  played  some  part  in  the  destruction  of  the  scale.  The  beetles 
winter  as  adults  and  have  been  seen  as  early  as  February  crawling 
over  the  bark  performing  their  useful  work.  Adults  of  the  beetle 
have  shiny  black  outer  wings  each  bearing  a  beautiful  spot  of  red. 
The  beetle  in  its  various  stages  is  shown  in  Fig  2. 

Last  summer  small  spiders  were  observed  destroying  the  newly 
hatched  scale  insects  upon  infested  pear  trees.  Webs  spun  across  the 


PLATE  II 


t2  THE  COLORADO  EXPERIMENT  STATION 

calyx  end  of  pears  were  found  filled  with  the  wings  and  remains  of 
male  scale  insects  which  had  been  entrapped  and  destroyed.  Unpro¬ 
tected  female  insects  were  also  found  to  have  formed  a  portion  of  the 
spider  s  food,  though  those  protected  by  scales  were  apparently  unmo¬ 
lested. 


FIGI  RM  2 

Lwice-s-tabbed  lady-beetle,  Chilocorus  bivu'nerua,  larva,  pupa  and  adult 
natural  size.  After  Bu  eau  of  Entomology,  Washington,  D.  C. 

Natural  enemies,  though  very  useful,  do  not  usually  succeed  in 
reducing  this  pest  to  a  degree  making  spraying  unnecessary. 

REMEDIES. 

Experiments  in  Mesa  County. — The  first  spraying  aga’nst  this 
insect  in  Mesa  county,  according  to  the  statements  of  local  fruit  grow¬ 
ers,  was  about  six  years  ago  when  the  finding  of  “scaly”  fruit  called 
the  attention  of  the  growers  to  the  necessity  of  steps  toward  control. 
The  first  material  used  seems  to  have  been  sprays  of  whale  oil  soap. 
These  sprays,  though  expensive  and  inconvenient,  proved  fairly  efficient 
in  the  hands  of  growers  thorough  in  their  methods  and  careful  in  pre¬ 
paring  the  mixture.  At  the  time  of  the  writer's  first  examination  of 
pear  orchards  in  the  Grand  Valley  many  were  found  which  had  been 
most  successfully  treated  with  the  lime-sulfur-salt  spray.  Great  va¬ 
riety  of  opinion  existed  regarding  the  method  of  preparation,  the 
proper  formulas  and  the  best  way  and  time  in  which  to  apply  the  spray. 
Sufficient  difference  of  opinion  existed  to  make  spraying  experiments 
advisable. 

Accordingly  the  pear  orchard  of  Mr.  Ray  D.  Garrison,  east  of 
Grand  Junction,  well  suited  to  the  experiment  was  selected  and  given 
treatment  with  the  permission  and  co-operation  of  the  owner. 

The  orchard  consisted  of  about  200  medium  sized  trees,  of 
Bartlett,  Clapp's  Favorite,  P.  de  Esta,  Buerre  de  Anjou  and 
Flemish  Beauty  varieties,  the  last  being  largely  left  untreated  the  pre¬ 
vious  year  and  now  thickly  covered  by  the  scale.  The  spraying  was 
done  April  3,  5  and  6,  1906,  just  before  the  opening  of  the  fruit  buds, 
and  a  thorough  coating  was  given  to  all  parts  of  the  tree.  Upon  all 
plats  spraying  was  done  with  the  same  degree  of  thoroughness.  The 
insecticides  used  were  variations  of  the  lime  and  sulfur  washes,  kero¬ 
sene-lime  emulsion  prepared  by  combining  kerosene  with  lime,  and 
scalecide. 

Scalecide  is  an  oil  treated  chemically  so  that  it  may  be  mixed  with 
cold  water  without  separation.  It  is  a  commercial  product  and  is  sim- 


THE  HOWARD  SCALE  13 

pie  to  prepare  for  spraying.  It  requires  no  special  manipulation  and 
is  pleasant  to  apply.  Scalecide  was  sprayed  upon  trees  in  another 
orchard  and  gave  most  promising  results.  The  kerosene-lime  emulsion 
proved  a  failure,  as  too  great  difficulty  was  encountered  in  mixing  the 
materials. 

The  lime  and  sulfur  sprays  were,  from,  all  standpoints,  most  satis¬ 
factory.  They  were  used  in  the  experiment  as  follows : 

(1)  Rex  lime  and  sulfur,  diluted  i  to  n  with  cold  water. 

(2)  .  Rex  lime  and  sulful,  diluted  1  to  8  with  cold  water  and  15 
pounds  lime  added  per  50  gallons  spray. 

(3)  Time-sulfur-soda  wash  prepared  without  use  of  external 
heat  and  boiled  by  the  soda  and  heat  of  the  slaking  lime.  Thirty 
pounds  lump  lime,  15  pounds  sulfur  and  5  pounds  caustic  soda  per 
50  gallons  water  were  used. 

(4)  Time-sulfur  wash  prepared  in  the  usual  way  by  boiling  45 
minutes  with  external  heat  and  composed  of  15  pounds  lime,  15  pounds 
sulfur  per  50  gallons  water. 

A  portion  of  the  trees  were  left  unsprayed  for  comparison.  Before 
spraying,  counts  were  made  which  showed  69  per  cent  of  the  lice  living 
and  31  per  cent  dead  from  natural  causes. 

These  comparisons  for  all  plats  are  shown  in  the  following  table: 
LIME-SULFUR  WASHES  AGAINST  HOWARD  SCALE  ON  PEAR. 


« 

Spray 

Formula 

Cost 

per 

200 

gallons 

spray 

Date 

Spray’d 

Scales  on 
bark  Apr. 
25 

Per  cent 
dead 

Scales  on 
pears 
Aug.  17 
Per  cent 
pears  pit’d 

Commercial 
Rex  Lime- 
Sulfur 

Rex,  1  gallon 
Water,  11  gallons 

$4.15 

3-5  Apr. 

74.9 

-1.0 

do. 

Rex,  1  gallon 
Water,  8  gallons 
Lime,  2f  pounds 

$5.70 

6  Apr. 

85.2 

2.8 

Self-boiled 

Lime-sulfur 

soda 

Lime,  30  pounds 
Sulfur,  15  “ 

Caustic  Soda,  51b 
Water,  50  gallons 

$3.45 

6  Apr. 

95.0 

1.0 

Lime-sulfur 

Boiled 

Lime,  15  pounds 
Sulfur,  15  pounds 
Water,  50  gallons 
Boiled  45  min. 

$2.00 

5  Apr. 

93.8 

0.6 

Check 

Not  Sprayed 

48.0 

96.1 

The  above  spraying  observations  were  made  upon  both  treated 
and  check  trees  throughout  the  season.  Two  means  of  comparison 


14 


THE  COLORADO  EXPERIMENT  STATION 


•  indicated  the  results.  The  first  was  that  shown  in  a  count  made  April 
25,  of  living  and  dead  insects  upon  the  bark;  and  the  second,  of  more 
practical  interest,  a  comparison  shown  by  a  count  on  August  17,  at 
the  time  of  the  last  harvest,  of  the  number  of  pears  showing  pits  upon 
their  surfaces. 

COMMERCIAL  REX  MIXTURE. 

Rex  is  a  concentrated  lime  and  sulphur  mixture  prepared  by 
boiling  together  the  two  ingredients  until  combined  and  removing 
for  use  only  the  clear,  reddish  liquid  free  from  sediment.  It  is  a 
product  prepared  and  sold  by  Rex  Stock  Food  Co.,  of  Omaha,  Neb. 
It  has  been  formerly  used  as  a  stock  dip  in  the  West.  For  spraying, 
it  has  only  to  be  diluted  with  cold  water.  Lime  may  be  added  if 
desired.  The  lime  is  added  so  that  a  white  coating  may  be  left  upon 
the  tree  indicating  where  parts  have  been  completely  covered,  and  to 
hold  the  spray  temporarily  upon  the  surface,  causing  more  of  the  mix¬ 
ture  to  dry  and  adhere  than  would  do  so  if  applied  as  a  clear  liquid. 

Referring  to  the  preceding  table,  it  will  be  seen  that  both  strengths 
were  effective  in  reducing  the  number  of  scales  upon  the  trees  so  that 
injury  to  the  fruit  was  prevented.  The  slight  difference  in  their  effec¬ 
tiveness  may  be  practically  overlooked  when  these  two  results  are 
compare  with  the  96.1  per  cent  of  fruit  rendered  unfit  for  market 
upon  the  unsprayed  trees.  Some  of  the  infested  pears,  unsprayed, 
bore  at  picking  time  no  less  than  328  attached  scales  of  varying  sizes. 

The  scales  dead  upon  the  tree  on  April  25,  twenty  days  after 
spraying,  was  85.2  per  cent  upon  the  Rex  of  stronger  dilution,  and  74.9 
per  cent  dead  upon  trees  sprayed  with  the  weaker  mixture.  The 
action  of  all  lime-sulphur  sprays  is  continued  for  a  considerable  time 
after  spraying.  The  former  figure  represents  the  increased  effectiveness 
produced  by  an  increase  in  strength  and  the  addition  of  milk  of  lime. 
Both  may  be  classed  as  of  value  in  comparison  with  the  48  per  cent 
dead  upon  the  check.  It  will  be  remembered  31  per  cent  of  the  scales 
indicated  by  count  were  dead  at  the  beginning  of  the  experiment  and 
the  per  cent  scales  dead  as  counted  upon  April  25  on  sprayed  plats 
included  the  31  per  cent  shown  to  be  dead  from  natural  causes  without 
treatment.  The  per  cents  given,  therefore,  under  estimate  the  ratio 
of  benefit  actually  derived  from  the  sprays. 

In  summing  up  it  may  be  said  that  Rex  lime-sulphur  diluted  one  to 
eight  with  cold  water  with  lime  added  as  per  formula  is  an  effective 
spray  against  the  Howard  scale.  It  is  not  recommended  as  more 
effective  than  the  standard  orchard-boiled  lime  and  sulphur  washes. 
As  was  shown  by  experiment,  the  latter  were  slightly  more  effective 
than  the  Rex  even  when  used  at  the  stronger  strength,  but  the  ease 
and  convenience  of  preparation  of  the  Rex  recommends  it  to  the  use 
of  orchardists  not  fitted  with  the  appliances  for  boiling  their  own  spray. 
Some  growers  prefer  to  pay  more  for  material  and  save  the  time  and 
labor  of  preparing  their  own  mixture.  Examination  of  the  scales  shows 
them  more  loosely  attached  to  the  bark  than  is  the  San  Jose  scale, 
thus  affording  less  resistance  to  the  spray  in  coming  in  contact  with 
the  body  of  the  insect. 


THE  HOWARD  SCALE  15 

In  the  spring  of  1906,  in  the  orchard  section  of  the  Grand  valley, 
a  carload  of  30,000  pounds  of  Rex  was  used  experimentally  as  a  spray 
principally  against  this  insect,  and  in  the  spring  of  1907  five  car 
loads  were  shipped  into  the  above  section  for  use  against  this  and 
other  orchard  pests.  Upon  Howard  scale  results  have  been  satis¬ 
factory. 

The  spray  has  the  disadvantage,  as  a  commercial  product,  of  being 
subject  to  variation  in  strength  without  knowledge  of  the  consumer. 
The  orchardist  compounding  his  own  spray  material  may  feel  more 
confident  of  his  product. 

The  Rex  mixture  was  to  be  had  the  past  season  by  growers  at 
Grand  Junction  for  25  cents  per  gallon,  making  the  cost  of  200  gallons 
of  spray  of  the  recommended  formula  about  $5.70,  or  a  trifle  less  than 
3  cents  per  gallon. 

Lime:  and  Sulfur  Mixtures.  The  lime  and  sulfur  wash  mixed 
in  the  right  proportions,  properly  boiled  and  correctly  sprayed  is  the 
most  satisfactory  spray  thus  far  used  against  Howard  scale. 

Lime  and'  sulfur  was  originally  a  stock  dip  used  in  California 
and  was  first  demonstrated  to  be  of  value  as  an  insecticide  in  1886.* 
It  was  then  taken  up  as  a  scale  treatment  in  the  East  and  is  now  very 
widely  used  and  considered  the  standard  scale  remedy.  It  is  also 
valuable  as  a  dormant  tree  spray  against  many  other  insects  and  is 
of  known  fungicidal  value,  controlling  the  peach  leaf  curl  of  some 
states. 

Different  formulas  have  been  adopted  in  different  states.  Some 
recommend  slightly  more  lime  than  sulfur  in  order  to  insure  the  com¬ 
bining  of  all  sulfur.  Others  contend  that  equal  parts  of  lime  and 
sulfur  are  best  when  a  strong  quick  lime,  high  in  calcium,  is  used. 
The  belief  that  equal  portions  of  lime  and  sulfur,  as  a  rule,  produce 
as  strong  a  solution,  chemically,  as  is  possible  to  secure,  is  endorsed 
in  a  recent  bulletin  by  J.  R.  Haywood  of  the  Bureau  of  Chemistry* 
The  addition  of  salt  formerly  recommended  may  be  safely  discontinued. 
It  adds  nothing  to  the  killing  effect  of  the  spray,  increases  cost,  makes 
the  spray  more  unpleasant  to  use  and  harder  upon  machinery.  The 
addition  of  copper  sulphate  (blue  vitriol)  to  the  formula  has  been 
recommended  by  some  experiment  stations,  by  others  it  is  considered 
without  insecticidal  value,*  and  by  some  it  is  regarded  as  a  positive 
injury  to  the  insecticide  properties  of  the  spray.* 

Variety  of  practice  in  the  preparation  of  the  spray  is  to  be  found. 
All  methods  provide  for  chemical  union  between  lime  and  sulfur 
brought  about  by  heating  with  water.  The  heat  may  be  supplied 
in  a  variety  of  ways  externally  and  the  spray  has  been  made  by  heating 
with  caustic  soda,  potassium  sulfide  or  an  increased  amount  of  Quick 
lime. 

The  so-called  self-boiled  lime-sulfur-soda  wash  used  in  the  experi- 

*  Bulletin  No.  1 66,  Calif.  Agr.  Exp.  Sta.,  1905. 

Bulletin  No.  101,  Bur.  of  Chem.  U.  S.  Dept,  of  Agr.,  Feb.,  1907. 

*  Ill.  Agr.  Exp.  Sta.  Bulletin  No.  107,  1906. 

*  Wash.  Agr.  Exp.  Sta.  Bulletin  No.  76,  1906. 


THE  COLORADO  EXPERIMENT  STATION 


1 6 

ment  referred  to  is  a  common  formula  where  both  quick  lime  and 
caustic  soda  produce  the  heat  of  the  mixture.*  Another  formula 
sometimes  used  by  growers  provides  for  an  excess  of  quick  lime  to 
produce  the  boiling  heat.  Others  use  this  method  except  that  hot  water 
is  required  to  quicken  the  slaking  process.  The  formula  using  caustic 
soda,  probably  the  best  of  the  above  self-boiled  mixtures,  though 
saving  cost  of  boiling  by  fire,  increases  the  cost  of  the  mixture.  At 
average  local  prices  at  the  point  where  the  experiment  was  conducted, 
the  cost  of  the  mixture  was  $3.45  per  200  gallons  as  compared  with  $2 
per  200  gallons  for  the  standard  orchard-boiled  wash. 

It  has  seemed  to  the  writer  that  attempts  at  preparing  the  mix¬ 
tures  without  the  aid  of  external  heat  has  usually  resulted  in  leaving 
a  portion  of  the  sulfur  uncombined.  This  is  indicated  by  the  yellow 
color  of  the  mixtures  so  prepared.  A  wide  difference  in  the  color 
of  the  sediment  was  noted  in  the  mixtures  prepared  by  different 
methods  in  the  experiment.  The  ratio  of  sediment  to  liquid  also 
showed  wide  differences.  The  strength  of  the  lime-sulfur  wash  will 
depend  upon  the  strength  of  the  soluble  portions  and  upon  the  sedi¬ 
ment.  The  sediment  is  supposed  to  gradually  decompose  into  nascent 
sulfur,  which  remains  upon  the  tree  and  continues  destructive  to  insect 
life  for  a  considerable  time.  An  excess  of  coarse  sediment  in  the 
spray  is  a  disadvantage  in  that  it  clogs  the  nozzles  and  increases  the 
wear  on  the  pump. 

Lime-sulfur  washes  were  originally  boiled  by  fire  two  hours  or 
more.  Later  observations  show  that  less  time  is  sufficient.  About 
forty-five  m’nutes  will  generally  form  as  effective  a  spray  as  can  be 
secured,  though  the  proper  time  required  for  boiling  must  be  indicated 
by  the  changing  of  the  undiluted  mixture  in  the  boiling  vessel  from 
a  yeflowish  to  a  dark  amber  color.  A  properly  boiled  mixture,  after 
diluting  for  spraying,  will  be  of  a  reddish  orange  color  and  have  a 
greenish  sediment.  The  lime  and  sulfur  should  be  boiled  in  about 
one-fifth  the  total  amount  of  water  and  then  diluted  with  either  hot  or 
cHd  wMtt  to  make  desired  quantity  of  spray.  Undiluted  mater'al 
should  not  be  allowed  to  remain  over  night  in  the  boiling  vessel,  for 
it  will  harden.  Standard  lime-sulfur  mixture  is  intended  for  imme¬ 
diate  use.  So  caustic  is  the  spray  that  the  hands  of  one  using  it  should 
be  protected  by  gloves.  Apparatus  should  be  rinsed  with  water  each 
time  after  using. 

Directions  tor  Preparing  Standard  Lime-Sulfur  Wash. 
The  following  formula  and  brief  description  for  preparation  of  a 
small  amount  of  the  standard  lime-sulfur  wash  is  recommended  for 
Howard  scale. 

Formula. 


Quick  or  lump  lime  . 15  pounds 

Flour  or  flowers  of  sulfur . 15  pounds 

Water . 50  gallons 


To  prepare  fifty  gallons  of  spray  place  seven  to  ten  gallons  of 


*N.  Y.  Agr.  Exp.  Sta.  Geneva,  Bulletin  No.  247. 


THE  HOWARD  SCALE  17 

water  in  the  boiling  vessel.  While  the  water  is  being  heated  by  a  hot 
file,  mix  in  a  separate  vessel  fifteen  pounds  sulfur  with  enough  water 
to  form  a  thin  paste.  Add  this  sulfur  paste  to  the  water  and  bring 
the  mixture  to  a  temperature  just  below  the  boiling  point.  Now  add 
fifteen  pounds  good  lump  lime.  A  violent  slaking  will  at  once  take 
place.  Keep  cold  water  at  hand,  adding  if  necessary  to  prevent  boiling 
ovei  the  sides  of  the  vessel  or  to  keep  the  mixture  from  becoming 
too  thick.  After  the  lime  has  ceased  slaking,  keep  steadily  boiling  for 
forty-five  minutes,  stirring  almost  constantly,  when  it  will  be  ready 
for  dilution  with  hot  or  cold  water  to  make  up  fifty  gallons  of  spray. 
It  is  then  ready  to  be  strained  and  applied. 

Time  to  Spray.  Late  spring  will  be  the  best  time  to  spray  for 
this  insect,  though  a  fall  application,  after  the  leaves  are  off,  will  be 
effective.  It  should  always  'be  borne  in  mind  that  the  lime-sulfur 
wash  is  a  caustic  spray  designed  only  for  dormant  trees  and  not  to 
be  sprayed  upon  trees  in  foliage.  Late  spring  is  preferable  to  early 
spring  sprayings.  It  should  not  be  delayed  too  late  lest  there  be  danger 
of  injuring  the  tender  fruit  buds.  Pear  buds,  though  swpllen  may, 
ordinarily  be  sprayed  with  safety  even  when  the  minute  green  leaves 
are  showing  beyond  the  tips  of  the  bud  scales.  After  the  green  leaf 
rudiments  are  in  view  a  cluster  of  rudimentary  pears,  each  borne  by 
separate  pedicel  or  stalk,  will  be  found  within  each  swollen  bud. 
One  may  probably  spray  with  the  mixture  up  to  the  time  these  bloom 
stalks  separate  into  distinct  buds,  just  before  unfurling  their  first 
petals. 

Orchardists  should  begin  their  spring  spraying  for  this  pest  in 
ample  time  so  that  it  may  be  completed  before  it  is  too  late.  The  time 
allotted  will  depend  upon  local  conditions  such  as  size  and  number  of 
trees,  and  kind  of  apparatus. 

Application.  Success  in  spraying  against  this  insect,  as  with 
others,  depends  more  upon  the  thoroughness  with  which  the  spraying 
is  done  than  upon  any  other  detail.  All  portions  of  the  tree,  from 
the  tip  of  the  twigs  to  the  base  of  the  trunk  must  be  completely 
coated.  Trees  must  be  sprayed  from  all  directions.  Strong  winds 
at  time  of  spraying  will  sometimes  make  this  a  difficult  undertaking. 
The  tips  of  twigs  around  the  outside  of  the  tree  and  in  the  top  should 
not  be  neglected.  Fortunately  the  spray  is  of  such  a  color  that  parts 
of  the  bark  left  uncovered  may  be  readily  detected.  If  such  spots 
can  be  found,  the  spraying  there  should  be  repeated. 

Apparatus.  Kind  of  apparatus  used  in  preparing  the  wash  will 
depend  largely  upon  the  amount  to  be  used. 

Prepored  in  a  small  way,  iron  kettles  are  found  suitable,  such 
as  are  shown  in  plate  I.  fig.  II.  For  small  amounts  a  very  convenient 
and  inexpensive  boiling  vat  is  made  with  No.  18  sheet  iron  bottom 
with  fourteen-inch  planks  for  sides.  The  ends  of  the  tank  are  formed 
by  bending  upward  the  two  ends  of  the  iron  bottom,  without  forming 
sharp  angles.  The  outside  dimensions  are  6  ft.  by  2  ft.  6  in.  Before 
nailing  on  the  iron  bottom  to  the  edges  of  the  plank,  insert  a  strip 
of  felt  between  wood  and  iron  and  coat  with  a  heavy  lead  paint.  Nail 


THE  COLORADO  EXPERIMENT  STATION 


1 8 

on  the  sheet  iron  tightly  and  mount  the  tank  upon  brick  sidewalls. 
A  low  brick  chimney  is  constructed  at  the  rear  connecting  with  the 
fire  box  beneath  the  vat.  Such  a  vat  is  large  enough  to  prepare  200 
gallons  of  spray  or  more  at  once.  There  are  many  of  these  vats 
used  about  Grand  Junction. 

Boiling  lime-sulfur  with  steam  is  by  far  the  best  method.  Portable 
steam  cookers,  such  as  are  used  for  cooking  stock  food  ,are  suited 
admirably  to  the  purpose.  Some  spray  machinery  manufacturers  have 
boilers  on  the  market  well  adapted  for  this  work.  With  them  the 
boiling  may  be  done  in  wooden  barrels.  A  steam  pipe  or  coil  from  the 
boiler  is  directed  into  the  mixture  and  the  strong  jet  of  steam  auto¬ 
matically  stirs  the  liquid  while  the  boiling  is  progressing. 

Where  large  quantities  are  to  be  prepared,  a  steam 
boiling  plant,  such  as  the  one  shown  in  plate  I,  fig.  I, 
will  be  needed.  This  plant  is  built  upon  most  improved  and  modern 
ideas  and  is  found  indispensable  for  preparing  lime-sulfur  wash  upon 
the  240-acre  orchard  of  Mr.  John  Ashenfelter  at  Montrose.  A  large 
steam  engine  beneath  supplies  the  steam,  which  is  conducted  in 
pipes  into  the  boiling  barrels,  ten  of  which  are  arranged  in  a  row 
upon  an  elevated  platform.  At  one  end  of  the  building  and  at  a 
higher  level  are  the  water  storage  tanks  filled  by  gravity  and  supply¬ 
ing  the  water  for  boiling  and  dilution.  The  small  building  at  the  rear 
is  built  for  a  storage  warehouse.  The  plant  has  a  boiling  capacity  of 
400  gallons  of  spray  and  the  boiling  barrels  are  emptied  by  gravity 
directly  into  the  spray  tank.  The  photo  shows  one  spray  tank  in 
process  of  being  filled. 

The  material  may  be  applied  by  good  strong  hand  pumps  or 
larger  spray  outfits.  A  large  number  of  gasoline  power  sprayers  are 
in  use  for  applying  the  mixture  in  the  Grand  Valley.  Long  spray 
poles  and  long  lengths  of  hose  are  desirable.  Nozzles  of  larger  aper¬ 
tures  than  those  used  where  a  fine  mist  is  desired  are  preferable. 

A  well  appointed  equipment  will  greatly  lessen  the  cost  and  incon¬ 
venience  of  lime-sulfur  spraying  against  the  Howard  scale.  This  is 
important  since  lime-sulfur  spraying  has  become  an  essential  part  in 
the  routine  of  orchard  work. 

BIBLIOGRAPHY. 

Aspidiotus  howardi  Ckll.,  Can.  Ent.  XXVII,  p.  16  (1895) 

Aspidiotus  howardi  Ckll.,  Bull.  19,  N.  Mex.  Kxp.  Sta.,  p.  106  (1896) 
Aspidiotus  ( Diaspidiotus )  howardi  Ckll.,  Bull.  6,  l1.  S.  Dept.  Ag.,  p.  21 
(1897) 

Aspidiotus  howardi  Ckll.,  Gillette,  Bull.  38,  Colo.  Exp.  Sta.  p.  37  (1897) 
Aspidiotus  (Aspidiella)  howardi  Leon.,  Kiv.  Pat.  Veg.,  VI,  p.  229  (1898) 
Aspidiotus  howardi  Berl.  e  Leon,  Annali  di  agr.,  p.  107  (1898) 

Aspidiotus  howardi  Ckll.,  Forbes,  20th  Rept.  Ins.  Ill.,  p.  16  (1898) 
Aspidiotus  howardi  Ckll.,  Newell,  Contr.  la.  Ag.  Coll.,  No.  3,  p.  10  (1899) 
Aspidiotus  (Aspidiella)  howardi  Leon.,  Gen.  e  Spec.  Diaspiti,  Asp.  p.  55 
(1900) 

Aspidiotus  howardi  Ckll  ,  Gillette,  Rept.  of  Entomologist,  Colo.  Agr. 
Exp.  Sta.  p.  16,  (1901) 

Aspidiotus  howardi  Ckll.,  Gillette,  Rept*  of  Entomologist,  Colo.  Agr. 
Exp.  Sta.  p.  7  (1902) 


THE  HOWARD  SCALE 


Aspidiotus  howardi  Ckll. 
(1906) 

Aspidiotus  how'irdi  Ckll., 
(1907) 


Gillette,  Bull.  114,  Colo.  Agr.  Exp.  Sta.  p.  16 
Taylor,  Press  Bull.  30  Colo.  Agr.  Exp.  Sta. 


SUMMARY. 

(1)  1  he  Howard  scale  is  present  in  injurious  numbers  in  many  fruit 
orchards  of  Colorado. 

(2)  The  pest  was  first  discovered  in  this  state  and  is  supposed  to 
have  originated  upon  plants  native  to  the  locality. 

(3)  It  is  less  destructive  than  the  San  Jose  scale  which,  so  far  as 
is  known,  is  not  present  in  the  state. 

(4)  The  insect  has  been  found  to  infest  many  varieties  of  fruits,  but 
is  primarily  a  pest  of  pear,  plum  and  prune. 

.  (5)  Damage  may  result  from  the  insects  attaching  themselves  to 

either  tree  or  fruit,  where  they  absorb  the  sap  as  parasite.  Trees  may  be 
killed  outright  or  fruit  may  be  rendered  unmarketable  from  its  “scaly” 
appearance. 

(6)  The  insects  when  attached  to  the  surface  of  fruit  or  tree  are 
of  minute  size — about  the  size  of  a  pin  head. 

(7)  By  rapid  rate  of  increase  they  may  produce  enough  individuals 
to  completely  encrust  the  surface  of  the  plant  attacked.  It  is  their  rate  of 
increase  and  gregarious  habit  of  life  which  make  them  so  destructive. 

(8)  The  female  insects  are  wingless  throughout  their  entire  lives  and 
except  for  a  short  period  following  hatching  are  entirely  motionless. 

(9)  The  spread  of  the  insect  is  dependent  largely  upon  agencies  out¬ 
side  the  control  of  the  insect. 

(10)  Samples  of  scale  insects  found  upon  fruit  trees  should  be  sent 
to  the  entomologist  of  the  Agricultural  Experiment  Station  for  determ¬ 
ination. 

(11)  Natural  parasites  and  predaceous  insects  preying  upon  the  pest 
do  much  to  hold  it  in  check  but  have  not,  in  the  past,  increased  enough  to 
make  other  measures  unnecessary. 

(12)  The  lime-sulfur  wash  applied  in  late  spring  before  the  buds  open 
has  been  found  a  complete  and  practical  remedy. 


KEY  TO  ILLUSTRATIONS. 


Plate  I. — I,  Plant  for  steam  cooking  several  barrels  of  lime-sulfur 
mixture  at  once,  owned  by  Mr.  John  Ashenfelter,  Montrose,  Colo.;  II, 
cooking  lime-sulfur  in  kettles;  III,  Aspidiotus  howardi ,  (A)  scales  upon 

pear  twig,  (B)  dead  females’  scales  of  last  year,  (C)  young  living 
female  scales,  (D)  adult  male  scales,  a  male  emerging  at  d — all  enlarged 
seven  times — drawn  by  Miriam  A.  Palmer;  IV,  photo  of  dead  and  living 
scale  upon  prune  twig,  considerably  enlarged;  V,  pear  showing  large  scales 
in  depressions,  also  young  white  scales  scattered  about,  somewhat  enlarged; 
VI,  pear  with  scales  removed  showing  pits  caused  by  the  lice. 

Plate  II. — Howard  scale,  Aspidiotus  howardi  Ckll.  I,  Pygidium  of 
female  showing  dorsal  characters  on  the  left  (A),  and  ventral  characters  on 
the  right  (B),  a,  wax  ducts;  b,  oval  dorsal  glands;  c,  grouped  ventral  glands, 
X  190;  II,  the  same,  showing  variation  in  the  number  and  form  of  the 
glandular  hairs  or  plates;  III,  newly  hatched  young,  x  95;  IV,  adult  male, 
X  62.  Original  drawings  by  Miss  Miriam  A.  Palmer. 

Fig  I. — Howard  scale  parasite,  Prospalta  aurantii  greatly  enlarged. 
After  L.  O.  Howard,  Bureau  of  Entomology,  Washington,  D.  C. 

Fig.  2. — Twice  stabbed  lady-beetle.  Chilocorus  bivulverus ;  larva,  pupa 
and  adult  enlarged  and  the  adult  natural  size. 


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UNIVERSITY  OF  ILLINOIS-URBANA 

630.7C71B  nmuc.001 

BULLETIN.  FORT  COLLINS 
102-120  1905-07 


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